SUPPLEMENTARY REPORT OF THE MAA ARG
President's Task Force on the NCTM Standards
This supplement to our task force's main
report on the NCTM Principles and
Standards for School Mathematics contains more specific comments and
suggestions made by individual members of the task force.
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CHAPTER 2: Guiding Principles
[Alan Tucker]
Equity Principle - well done. My only comment is that I would like
to see in writing the point that I heard at a meeting from one of the PSSM
authors: a higher level of knowledge for all students raises the baseline
above which an even higher standard for talented students can be developed.
Today, many talented students just get an 'accelerated' program that covers
topics at the rate that average students in other countries do. "A rising
tides lifts all ships."-- while possibly simplistic, this reasoning has
much to recommend it and seems to be a politically savvy way to offer
everyone much of what they want.
Mathematics Curriculum Principle. The discussion does not develop
the concern about focused instruction adequately-- the second paragraph in
this section (page 27) is a good start. The subsection 'Choosing
Mathematics that is most important' is meaningless without lots of
examples. The important concerns of "coherence" and "comprehensiveness" in
the curriculum are discussed too vaguely.
Teaching Principle. The 'Analysis and Reflection' part is much too
vague-- no guidance about what is wanted in the classroom. This would be a
good place to honestly address the challenge of getting the right balance
between drill and exploratory activities.
Learning Principle. This is the section that consistently plays down
mastery of skills and says virtually nothing positive about such mastery,
e.g., in the first paragraph we find "Students' ability to provide correct
answers is not always an indicator of a high level of conceptual
understanding." The subsection 'Building on Prior Experiences . . ' is
feel-good, e.g.,. "... become members of a mathematical community" but
largely useless in guidance for day-to-day teaching. The subsection
'Learning Concepts and Procedures' is the one that really damns skills with
faint praise.
Assessment Principle - generally well done. The explicit refusal to
give grade-by-grade outcomes appears on line -4 of page 37. Page 39,
paragraph 2 is too negative about the value of national tests, like the
proposed 8th grade test. Page 40, paragraph 3 is too negative about grades
for students. Again, why go needlessly out of one's way to antagonize the
mainstream thinking in the country. This should be a consensus building
document.
Technology Principle - reasonable and balanced. Because of the
politically charged aspects of technology substituting for drill, the
authors should be more careful in the paragraph on page 43 about
calculators: the fifth sentence about the need for arithmetic skills should
come earlier in the paragraph and should be stated more positively.
[Deborah Tepper Haimo]
As for technology, the document, in the introduction as well as in other
sections, does mention that students need to become fluent in basic facts,
but this always seems to be downplayed. I believe it important to stress
that students need to master fundamentals and not turn to technology for
simple arithmetic facts that should have become second nature.
[Henry Alder]
There are other places where the Draft is lacking in specific guidance and
where teachers will clearly look for it. For example, see the statement on
"Calculators" on page 43 where it is stated on line 5 that "Students at all
levels should have access to calculators and other technology as they solve
problems" and on line 8: "However, access to calculators does not replace
the need for students to learn and become fluent with basic arithmetic
facts.." No guidance is provided how both of these goals can be achieved
simultaneously.
The Draft is completely silent on many other factors which need to be in
place for mathematics instruction to be successful. Among the host of
other programmatic matters, I would add the importance of uninterrupted
classroom instruction, the special importance for students to attend
mathematics classes, what constitutes a good lesson (as learned from some
of the TIMMS studies), and the importance of parent involvement. I am not
suggesting that many pages be devoted to these important factors, but
rather that a concise coverage be included emphasizing what is essential
for each of these factors.
[Stephen Rodi]
At this point in my reading [Standard 5], I decided that the Principles
document would have more chance for positive impact on mathematics
instruction in the U.S. if it expanded Chapter Two (pages 21 to 43) beyond
generalities to include detailed, specific, hard-nosed direction on course
content, course sequencing, hours of instruction, teacher training, teacher
certification, use of homework and a host of other pragmatic matters which
make the real difference in how much mathematics students learn. (I know.
For better or for worse, education is a local matter.)
[Henry Pollak]
Page 37, figure 2.1. I see this as a DIRECTED graph going from N to E to
S to W. I am not convinced of the link from W to N.
[Mercedes McGowen]
The authors have stated several of their underlying assumptions,
particularly in Chapter 2: Guiding Principles. These are elaborated on and
clarified in the following chapters. However, as the document is currently
organized, one has to search through several chapters and put the pieces
together in order to have a clearer understanding of what these assumptions
and hypotheses are. I was expecting that our responses would, at the very
least, speak to the beliefs that are explicitly stated in Chapter 2, as
they are the foundation for the recommendations in the subsequent chapters.
Do we agree with or support these beliefs? As outlined in the draft, they
call for some very different instructional practices than are currently in
use in many schools.
A basic assumption about learning mathematics is stated in the Learning
Principle (p. 34), namely: people do not generally learn concepts by
building up pieces of knowledge but rather from grappling with complex and
interesting tasks. This assumption about how students learn implicitly
challenges the belief that students must learn skills BEFORE they attempt
to tackle complex problems. In the past, this has been misconstrued to
imply that students do not need to learn skills. The issue many of us
wrestle with is not whether to teach skills and algorithms, but WHEN to
teach them and HOW to teach them so that students develop meaningful
understanding and retain their knowledge in long-term memory. It is at the
heart of much of the current debate. It has been argued that students
can't use calculators until after they master basic facts; they can't use a
symbolic manipulator until after they can do the algebraic manipulations by
hand. They can't do word problems until they learn the procedures, etc.
The issue is not whether students use calculators, or symbolic
manipulators, but what tasks they are asked to do and for what purpose.
Let's focus on what skills, besides knowing basic arithmetic facts, we want
students to KNOW upon completion of high school and address the issue of
how those skills might differ, in degree, in complexity, in number,
etc. for mathematically able students and for students who are not
intending to take advanced mathematics. Is it the same set of skills and
understandings for both groups? Alan Tucker raised the issue with his
question about the two mathematical goals besides the traditional
preparation for calculus. Should we not provide the authors of PSSM with
some statement regarding these issues?
What UNDERSTANDINGS do we want students to have, in addition to "skills"?
We have been quite silent on this point, focusing mostly on the need for
basic skills.
[Bob Megginson]
In general, this chapter does a good job of laying out the principles
guiding the Standards, although it does so better for some of the standards
than others.
Below are some specific comments on the draft.
page 21, lines 4-26: The statement about the need for well-taught
mathematics, and the references to the importance of technology and
professional development programs, is good.
page 22, lines 1-2, 8-9: The difference between the statements of
the Equity and Learning Principles is too subtle. In particular, if
"learn" were substituted for "understand and use" in the Learning
Principle, then the two would become indistinguishable. The Learning
Principle should be reworded to something like this: "Mathematics
instructional programs should enable all students to understand mathematics
conceptually, not just as a collection of facts and skills, and be able to
apply the material in situations not necessarily anticipated during
instruction."
The Equity Principle
page 23, lines 15-22: The analogy between "mathematics for all" and
"English for all" is a very strong and well-put statement about the need
for the Equity Principle. It should be kept.
page 25, lines 5-16: If the cited research actually shows that
achievement by females has increased to match that of males, rather than
that the "gender gap" is closing only because of decreased achievement by
males, then this should be said explicitly.
page 25, lines 26-29: It is true that "Schools in middle- and
high-income communities are typically able to attract better qualified
mathematics teachers than schools in low-income communities." However, a
lot of highly dedicated and exceptionally hardworking teachers in
low-income school districts, some of whom I have had the pleasure to work
with as they have sought to upgrade their mathematical abilities, are quite
fed up with hearing that the education in these districts is so bad because
the low-paid help is incompetent. The first sentence of this paragraph
should be replaced with something like this: "Schools in middle- and
high-income communities are typically able to afford a higher-quality
educational experience for the students than schools in low-income
communities, including a variety of instructional materials and good
professional development opportunities for the teachers."
page 26, line 1 through page 27, line 5: The emphasis on
research-based analyses of differential performance of students from groups
traditionally underrepresented in mathematics is very good, since it
addresses the perception voiced by some critics of the current Standards
that there is no research basis for modifying or expanding classroom
approaches to address the needs of such students. The additional emphasis
on holding high expectations of all students, but also making sure that
they are provided with the means to satisfy those expectations, is also
very good.
The Mathematics Curriculum Principle
The stress throughout this section is that
... the mathematics included in school programs should be sound,
significant, and important. Areas of mathematical content and process
selected for inclusion need to be arranged into coherent, comprehensive
curricula that foster mathematical development over time." (page 27, lines
29-32).
In general, this section conveys this message well.
page 28, lines 13-16 and 32-35; page 29, lines 26-27 and 36-37: It
is stated here directly and clearly that rigor, sound arguments, the
axiomatic nature of mathematics, and procedural competence are important,
as is knowing when to use technology (and therefore when not do so). It is
also stated that the emphasis should not be entirely on conceptual
knowledge and mathematics that derives from real-world applications. These
points are excellent and should be kept.
page 29, lines 23-25: Those who advocate one single national
mathematics curriculum for all precollege students could quote the
statement that "these standards should consititute the core curriculum for
all students" as evidence that the NCTM does not in principle oppose such a
notion. I suggest changing "constitute the core curriculum" to "form the
basis for the curriculum".
The Teaching Principle
This is a good, solid statement about the need for competent and caring
teachers. It is particularly good that it is stated clearly that "Such
teaching (to create a classroom environment for thinking and learning) can
be accomplished only by teachers who have had strong preparation and who
will have ongoing access to effective professional development" (page 30,
lines 23-24), and "teachers need to know mathematics well beyond the
mathematics they teach" (page 31, lines 17-19).
page 31, lines 31-38: This paragraph is a good statement of the
need for a mixture of classroom approaches if a teacher is to reach all
students effectively, and it is wise (and correct) to include "direct
telling" as an example of one strategy that is often appropriate.
page 32, line 1 through page 33, line 15: These subsections on
learning environments and student in-class discourse are more about the
core content of the college preparation of every teacher than mathematics
standards. Cuts should be made here.
The Learning Principle
This section is more vaguely written and less focused than its
predecessors. In particular, the introduction on page 33, line 21 through
page 34, line 30 could be tightened up. What it basically says is that (1)
in their school years, students should acquire a solid understanding of the
conceptual basis underlying school mathematics; (2) such understanding is
not the same as the ability to repeat memorized facts and display practiced
skills; (3) this conceptual understanding begins with ideas formed about
mathematics even before reaching school and should grow as students
progress through the grades; and (4) in building on the prior knowledge
that students have, teachers must consider both the knowledge base that the
class has as a learning community and the differing ones held by students
as individuals. It should not take so much space to say this.
page 34, line 32 through page 35, line 21: The entire first
paragraph of this three-paragraph subsection on "Learning Concepts and
Procedures" could be omitted, and the important points would still be made.
This would also remove the reference to "so-called prerequisites" that some
will view as inflammatory.
page 35, lines 17-21: The examples given here of student mistakes
due to conceptual misunderstandings could just as easily be examples of
mistakes due to procedural misunderstandings; students with little
understanding of concepts but a solid understanding of procedures would
still not make these particular mistakes. Better examples should be sought,
or the ones already given should be reworded to show how they reflect
conceptual misunderstandings. For example, rather than presenting the
miscomputation 100 x 3.45 = 3.4500 as an error a student makes by relying
on procedure, it could be stated that a student with a solid conceptual
understanding would not be likely to make this error, since the growth of
the number 3.45 by a factor of 100 will clearly not result in an answer
that is still equal to 3.45.
page 35, lines 22-35: This subsection could be made more concise
without substantial loss of content by omitting everything beginning with
"They should" on line 28 through "conceptual understanding" on line 32.
The material addresses principles that apply to all learning and is not so
important to include in a document specifically addressing mathematics
learning.
page 35, line 36 through page 36, line 16: The subsection on
"Active Engagement with Mathematics" and the concluding summary paragraph
for the entire section are fine and well stated.
The Assessment Principle
The writing in this section is direct and nontechnical, and therefore
likely to be easily understood by all who are interested in assessment,
teachers and nonteachers alike. The section begins with a solid statement
(pages 36-37) of the reasons for assessment, making it clear that the aim
is assessment of curriculum and progress toward school, regional, and
national goals as well as assessment of individual student progress. The
rest of the section, which focuses on the structure and process of
assessment, is also quite good. I have no suggestions to offer for change.
In particular, I really like the concrete example given on page 39, lines
16-25 of assessing student understanding of equivalent fractions beyond the
ability to apply an algorithm that constructs them.
The Technology Principle
page 40, lines 30-40: The introduction to this section, with its
emphasis on the responsible use of technology in the classroom, is good.
page 41, lines 1-12: I disagree that technology should be portrayed
as an effective tool for changing students' perception of mathematics as a
dead discipline. As mentioned, technology can be used effectively for
geometric visualization and the exploration of large data sets, but the
students will almost certainly recognize that these are applications of
technology to the better understanding of old knowledge. The portions of
cryptography that they can explore with understanding at the precollege
level, even with the use of technology, still seem to be rather classical,
and the presentations of fractals and chaos that I have seen given at the
precollege level seem to be quite descriptive, with technology used to
explore particular fractals in detail rather than to convey any real
understanding that there is new mathematics involved in analyzing what is
seen on the screen. I am not familiar with all of the materials used to
present these growing fields to precollege students, so there may be much
here about which I am not aware, but I remain wary of touting technology as
a device for convincing precollege students that mathematics is a rapidly
growing subject.
page 41, line 13 through page 42, line 41: This subsection
discusses the real value of technology in the mathematics classroom,
namely, to aid mathematical explorations that would be overly tedious or
otherwise impractical without the technology. The example of a young
student exploring which numbers one can count by to arrive exactly at 100,
and then (we hope) exploring some of the mathematical questions that arise
from this, is good.
page 41, lines 37-38: It is not clear why "Children can study
graphs and tables at an earlier age when they have technological help to
generate them," though technology can certainly help with the exploration
of complicated graphs and large tables at any age.
page 42: This entire page is a solid, well written statement of the
importance of technology in the modern mathematics classroom. The caveats
in the last paragraph, particularly the strong statement ending this
subsection that "The technology should be used to support conjecture, but
teachers need to provide an emphasis on the importance of proof," are quite
appropriate and welcome.
page 43: This page is the document's statement about the use of
calculators and other technology. Due to the controversy surrounding this
issue, this must be said very carefully. As it now stands, the statement
that "Students at all levels should have access to calculators and other
technology to use as they solve problems" (lines 5-6), and later statements
about giving students "routine access" to technology so that it is
"available when needed," are open to misunderstanding and quotation out of
context. The document seems to imply that there are situations in which it
is appropriate not to allow students to use technology, and that "routine
access" to technology need not be given when the students are tested on
their mastery of basic skills, but it never flatly says so. It should
flatly say so. After all, students also use books extensively in their
everyday lives and will be expected to be able to learn from them in the
workplace, but this does not mean that all tests must be open-book.
CHAPTER 3: Overview of the Standards
[Henry Pollak]
The four societal needs on page 46 should really be five. What's missing
explicitly is the mathematics of intelligent citizenship. Number 2 is
called "Cultural Literacy", and says what "our citizens" should learn. But
what is being learned here is cultural literacy. Then in Number 3, it says
"Just as the level of mathematics needed for intelligent citizenship has
increased..." - as if that's what the previous paragraph had talked about!
It seems to me that mathematical literacy is number 1, cultural literacy is
number 2, mathematics for intelligent citizenship is number 3, mathematics
for the workplace is number 4, and mathematics for client disciplines is
number 5. If the list of societal needs must be kept down to four, then
the workplace and the science and engineering and other users really go
together better than submerging intelligent citizenship between the second
and third.
In the parts that I read, the word "model" often means a mathematical
idealization of a phenomenon outside of mathematics (e.g. page 50, line 15
or page 307, lines 16 and 17). But sometimes the word "model" may mean a
mathematical reformulation, a different representation, of something
elsewhere in mathematics. That's the way I would read page 48, line 12 and
line 15. "Model" IS used in several ways in mathematics, and those are two
of them. They are different; this illustrates the value of a glossary.
It is asserted on page 46, line 22 that "the main topics of discrete
mathematics are included, but are distributed across the standards". Are
we sure? There is research by Harold F. Bailey, "The Status of Discrete
Mathematics in the High Schools", DIMACS Series in Discrete Mathematics and
Theoretical Computer Science, volume 36, "Discrete Mathematics in the
Schools", AMS and NCTM, 1997, pp. 311-316. The six topics of highest
frequency reported in that survey were, in order, set theory,
combinatorics, graph theory, functions and relations, trees, and
probability. I have seen the graph theory and the probability in my
reading so far; are the others covered?
[Deborah Tepper Haimo]
- There is one overall difficulty that disturbs me. It is the fact
that all results of mathematics are based on hypotheses whether these are
explicitly given at the start of a problem or are implicit and thus are
assumed to hold if any reasonable person would not dispute their existence.
In early grades, there is generally no problem, since what is given or
known is largely obvious so that no difficulties arise. As students move
ahead in mathematics, however, the fact that hypotheses are often not
explicitly given can be a problem both for students and their teachers.
For example, this turned out to be serious and was apparent in some of the
earlier NCTM materials where unnecessary mistakes were made. By ignoring
hypotheses, questionable results were obtained for problems highlighted as
vignettes. Such errors can and should be avoided by a clear statement to
the effect that a given set of hypotheses leads to a single correct answer
(even if there are various ways to arrive at a solution -- a fact that is
often stressed in these pages as it should be).
- Page 50, lines 33-34: I wonder about that last sentence. Do
students who have number sense really "NATURALLY decompose numbers, etc."?
I rather doubt this from my experience.
- Page 51, line 3 of last sentence: I would prefer deletion of the
last five words which seem to me unwarranted, and their replacement by
"with numbers are ready to advance in their study of mathematics."
- Page 51, lines 6-7: I would delete the words " the single digit",
"combinations and the counterparts for". I would start the next sentence
with "Understanding" and follow "skill" with "of such facts", deleting
"Understandings and skills can also be developed" at the beginning of the
next sentence which I would combine with the first by introducing the words
"as well as".
- Page 51, line 10: It might be preferable to have some parallel
structure by introducing the word "at" before "school".
- Page 51, lines 14-15: I suggest changing the end of the sentence to
"and in successfully studying many other areas of mathematics."
- There is much repetition of ideas, phrases, and words throughout the
document extending it to well over 300 pages! Will it really be read
by anyone? I guess the authors realized this, but they nevertheless
did not seem to restrict themselves, perhaps because of lack of time.
- Perhaps on page 51, line 16, the word "use" could be changed to
"will turn to".
- Page 51, lines 20-21: Replace the words "and that" with "to".
- Page 51, line 22: A plural is needed for the verb "help".
- Page 51, line 23: All that follows the second "and" would be
questionable. At least the word "will" should be replaced by "may".
- Page 51, lines 26-27: The words "and the inclination" might better
be replaced by "making sure", and the further repetition of "and
inclination" in the next line should be deleted. .
- Page 51, line 34: Why is it necessary to distinguish between
"estimation and approximation"? Are these terms clearly defined and
universally accepted by educators? I have asked several mathematicians
and they could not differentiate meaningfully between those terms.
- Page 51, last paragraph: This paragraph fails to stress how
important it is to know the basic arithmetic facts as well as those in,
say, the calculus. The first sentence might be completed by including the
statement "but all students must know thoroughly all the basic facts of
arithmetic without relying on calculators for such information." This
might be followed by "Only after they have mastered these facts is the
time appropriate to turn to calculators as computational tools to deal
with cumbersome computations necessary for solving some problems." The
rest of the verbiage is poor justification to introduce calculators
promiscuously into the mathematics classroom and is better omitted
entirely.
- Page 52, line 5: After "aided" add "when necessary".
- Page 52, line 6: Replace the first five words with
"manipulatives".
- Page 52, lines 11-13: Change "collected" to "gathered"; combine the
following sentences to read instead, "It may be that, in the early grades
for example, "24" is seen as ... twelve".
- Page 52, lines 29-39: What about more complex fractions such as 2/7
or 4/9? When are students exposed to these and their operations? Is
that included in the grades 6-8 material mentioned on the next page, at
the beginning of the first full paragraph?
- Page 53, line 31: Is the phrase "missing-addend situations"
conventional?
- Page 54, line 5: Add, after "identities", the words " for addition
and multiplication, respectively".
- Page 54, line 16: At some point, there was discussion of division's
relationship to subtraction. What is regarded as "inverse" here?
- Page 54, line 37: Who is the judge of "tedious"? Might not this
word be omitted?
- Page 55, line 16: Why not say "have memorized" rather than "be able
to recall"? Politically, memorization is out, but why?
- Page 55, line 31: Here also, "develop recall of" might be changed to
"memorize".
- Page 56, lines 19-24: I find it confusing to have patterns and
functions, which are generally regarded as parts of algebra and play a
role in its study, separated out as topics here. I would suggest that
the whole first paragraph be omitted.
- Page 56, line 26: Add, after "including", the words "the search for
patterns, the study of functions, ... notations."
- Page 57, line 5: Young children should be alerted to the fact that
when they are given a small number of terms their finding of a next term
or formula that generates what has already been given is only one
possible answer if nothing further is mentioned.
- Page 57, line 16: After the word "case", add "very likely".
- Page 57, line 21: After the word "generated" there might be a comma
and the continuation of the sentence to read "but should be aware that if
a general rule to describe the pattern is not given, they may find a
variety of possible generalizations that produce the same few given terms
at the start".
- Page 57, line 31: The wording can be considerably abbreviated here,
as elsewhere, without changing any meaning. Instead of the many
repetitions, after the sentence ending with "study", add a new one that
reads "As students continue in grades 9-12 and systematically consider
other families of functions, they use algebraic ideas to build on earlier
school experiences, and extend their knowledge by including polynomial,
rational, exponential, and trigonometric functions".
- Page 58, line 13: It would be wise, it seems to me, to avoid pompous
declarations, and the overused word "power" is a case in point. I would
thus recommend that the first four words of the second sentence here be
replaced by "It" and that the last four words be replaced by "finding a
solution".
- Page 58, line 15 : Aside from the word "power," which I again would
delete in favor of, say, "learning", I am concerned about the emphasis on
mathematical ideas encountering "conceptual obstacles" or being
"complex". It seems to me that the overall picture is of a discipline
too hard to learn. Why instill such negative thoughts in those who
should give every indication that they are involved with a dynamic,
exciting, and vibrant area of study?
- Page 58-60, lines 15-23: There is too much negativism here and far
too much detail. The entire section can be considerably shortened!
- Page 60, line 25: The entire paragraph here might read "Mathematical
modeling of phenomena provides an important application, symbolic
notation being central here with algebra implicit throughout." Again,
the rest of the section can be abbreviated considerably.
- Page 61, lines 11-13: The words "change" and "multiple" are too
vague here and need to be replaced.
- Page 76, line 5: An important part of understanding mathematics
might be to change the phrasing of the second bullet to read "develop the
ability to formulate problems by identifying hypotheses and conclusions,
to represent them in various ways, and to use algebraic notations to
abstract and generalize these". Why specify "outside mathematics" since
all examples seemingly outside the discipline will be dealt with by
mathematical tools?
- It is important that problem-solving not be confined to a set of
isolated situations that will fragment the discipline. For this reason,
it is vital that mathematical concepts be carefully considered and
mastered so that students have a sense of a well thought-out discipline
culminating in important results. Indeed, the same mathematical tools,
given different interpretations, can be applied to seemingly unrelated
disciplines to solve a highly varied array of problems in many different
areas if their essence is recognized.
- Despite the phrasing of needing to "develop a disposition," the mere
introduction of that noun furthers the prevalent notion that mathematical
talent is somehow innate and those without it cannot learn. I would by
far prefer to change the word "disposition" to "ability"!
- Page 76, lines 11-21: The paragraph might be changed to read
"Developing the ability to solve problems is important and should be a
well-integrated part of the curriculum. It requires finding a solution
method not known in advance, and consequently strengthens students' use
of the strategies they have learned. Students must be given ample
opportunity to deal with complex problems that require significant effort
to solve."
- Page 76, lines 22-37: The introductory questions are repetitive of
earlier discussion and should be omitted. The example for middle school
to provide some understanding of proportion seems confusing, particularly
if recipes have more ingredients than the same juice and water. (Is that
intended to be dealt with in what is in the parentheses?) The problem as
stated is far too vague to be considered a good mathematical
illustration, and much too much time seems devoted to getting the notion
of proportion across by this example.
- Page 77, lines 1-11: The paragraph might read as follows: "When
students learn a given concept such as the operations of arithmetic in
the lower grades, their knowledge should be reinforced with good
problems. For example, a teacher may say 'I have pennies, dimes, and
nickels in my pocket. If I take three coins out of my pocket, how much
money could I have taken?' (adapted from NCTM 1989, p. 24) The knowledge
needed to solve this problem is the value of the coins in question as
well as the operation of addition. Students must have content knowledge
to deal with problems, but they can determine the information they lack
and need if they have acquired real understanding of the concepts
involved."
- Page 77, lines 14-16: Delete this material.
- Page 77, lines 26-29: Replace the first sentence with "Individuals
who have mastered mathematical concepts tend to abstract and generalize
results. In the second sentence, after "individuals" add the word
"generally" and then delete "making ... and ".
- Page 77, line 31: At the end of the line, add "with equal horizontal
and vertical sides".
- Page 77, lines 34-35: The last sentence of the paragraph might read:
"These children have learned that there may be many ways to look at a
problem and finding one approach may not necessarily be a signal of being
finished. One may well seek another answer which may be shorter or more
elegant, highly prized in mathematics."
- Page 78, lines 4-16: Why are both examples for high schools?
- Page 78, lines 24-31: Most of the material in the paragraph has been
repeated many times and the paragraph should be deleted.
- Page 79, lines 7-8: Delete the entire second sentence. Add, at the
end of the third "and cannot be generalized."
- Page 79, lines 9-15: The last sentence there might read "Clearly
different strategies are accessible at different ages, including, for
example, the very specific and mathematically powerful proof by
contradiction, ... strategies."
- Page 79, lines 15-17: Delete the sentence there, and have as the
last sentence, " Strategies are learned over time, becoming increasingly
complex to deal with more involved problem situations."
- Page 79, lines 21-22: Add after "they" the words "should have
mastered". Delete the next sentence.
- Page 79, lines 22-24: After "They... problem" introduce a comma and
continue with "reading it carefully if it is written down and asking
questions until they fully understand it, if it is told to them orally."
Delete the sentence that starts with "Effective".
- Page 79, line 31: Delete the nine words beginning with "in" and
ending with "mind".
- Page 79, line 36: Add after "problems" the words "if these are not
isolated but clarify and enhance important mathematical concepts" with
appropriate commas.
- Page 79, lines 38-39: After the fourth word of line 38, "that", add
"stress the importance of developing such ability, consider a variety of
mastered strategies, do not hesitate to make adjustments and change
course if need be" to compete the sentence.
[Susanna Epp]
The subsection Standard 7, discussed on pages 80-85, is generally good to
excellent. My main reservation concerns the use of the words "convincing"
and "persuasive" to describe arguments, and this reservation applies to all
the many sections in PSSM where this language is used. The quote from John
Mason (page 81), "Convince yourself; convince a friend; convince an enemy,"
sounds great to a mathematician, but in the real world, rational thought
processes play only a small role in convincing or persuading anyone of
anything. In particular, they essentially never work with one's enemies,
and polite friends normally downplay disagreements of all kinds. That is
why it is difficult to get students to criticize each others' arguments in
a mathematics class.
[Mercedes McGowen]
As Deborah Haimo pointed out: "the fact that hypotheses are often not
explicitly given can be a problem both for students and their teachers." I
believe that we, along with the authors of PSSM, should also explicitly
state hypotheses AND underlying assumptions about teaching and learning
mathematics.
STANDARDS
STANDARD 1: Number and Operation
[Alan Tucker]
- K-2 The Focus Areas are good. The discussion is good except
on the lower half of page 114 and on page 115 where mastery of addition
facts is downplayed too much.
- 3-5 The Focus Areas and discussion are good. Informative
examples.
- 6-8 The Focus Areas and discussion are generally okay. The
second bullet "develop meaning for integers . ." in the 'Understand
Number. .' Focus Area seems to be a primary grade topic. The 2nd
paragraph on page 218 and the 3rd paragraph on page 219 seem to be
discussing material that should have been covered fully in earlier grades
-- there appears to be little new here.
- 9-12 The Focus Areas and discussion are good. I like the
emphasis on matrices and complex numbers.
STANDARD 2: Patterns, Functions, and Algebra
[Alan Tucker]
- K-2 The Focus Areas and discussion are reasonable (not much
going on for this standard at this level).
- 3-5 The Focus Areas and discussion are good. Reasonable
examples.
- 6-8 The Focus Areas and discussion are good. Nice examples.
- 9-12 The Focus Areas and discussion are good. However, on
page 281, paragraph 3, I'd like to see an explicit, positive statement
about the importance of mastery of symbolic manipulation skills.
As noted earlier, one curriculum for all high school students seems wrong
to me. Calculus in high school should be discussed. There are important
points to be made here, e.g., require students in AP calculus classes to
take the AP exam, rather than treat the course as a warm up for calculus in
college.
[Mercedes McGowen]
The discussions about representations and, in particular, about symbolic
notation, are found throughout the document in Standards 2 and 10. The
underlying assumptions on which the recommended changes in practice are
based are not stated directly and concisely in one place, but dispersed
throughout the document. These discussions recommend changes in
traditional teaching practices which, if widely adopted, would impact bench
marking and expectations about what students should be able to do at
certain specified times. The changes have not been noted or commented on in
any of the task force discussions to date.
In the content standards 1 and 2, the authors explicitly recommend that
"conventional symbolic representation and manipulation begins to be an
important part of the childs' mathematical activity toward the end of this
grade band." (p. 120, lines 1,2). They argue eloquently for allowing
children flexibility in their choice of representations and state that
teachers "should provide as many different representations as necessary" in
order that children might develop understanding of mathematical concepts
and procedures. (page 148, lines 4-5). The authors suggest that it would be
useful "to consider not only how conventional representations might be
better taught to students, but also to consider the role that other, less
conventional, representations might play in the mathematics classroom."
They support their recommendation on p. 95 and 95 (Chapter 3).
In the Grade 3-5 band, flexibility in choosing and creating
representations with discussion of the advantages and limitations of a
particular representation are discussed. Expecations are not stated
clearly for what skills and understandings students who complete 5th grade
should be able to demonstrate with respect to symbolic notation.
However, the discussion about structure and symbolic notation in the
Standards for 6-8 are quite specific (pages 224-226). A caveat is also
stated: "Learning to interpret and write symbolic expressions and to solve
symbolic algebraic equations is important in the middle grades, but for
most students extensive work with symbols should come only after they have
become fluent with verbal, tabular, and graphical representations of
relationships that symbols represent."
Once again, the PSSM recommendations explicitly challenge the traditional
practices of when symbolic notation is introduced and how it is introduced.
They also raise the question about what the 9th grade formal algebra course
should consist of. What is envisioned as content for middle grades students
is much of the foundation many students lack AFTER completing two years of
high school algebra as currently taught.
STANDARD 3: Geometry and Spatial Sense
[David Kullman]
I have no problems with the four points of the standard itself, nor with
most of the Focus Areas for specific grade bands. However, it isn't clear
to me what is meant by "use spatial orientation to navigate to a point"
(page 171, line 13) or whether "geometric relationships among
two-dimensional and three-dimensional figures" (page 227, line 18) refers
to each dimension independently or to some connections between them.
As I noted elsewhere, I think that the detailed examples are overdone. On
the other hand, the Focus Areas are vague enough that their implementation
may be accomplished in various ways, not all of which will meet OUR
interpretations of what the standards say.
[Bob Megginson]
General Discussion of the Standard
It is good that mention is made right up front about the role of geometry
in developing students' ability to "use formal reasoning and proof in their
study" (page 61, lines 34-35). This point is repeated at appropriate
places throughout the discussion of this Standard, for example, on page 62,
lines 21-26 and 34-36 and page 291, lines 20-22. Appropriate emphasis is
also placed on the use of technology to aid geometric visualization and
investigate geometric conjectures, but the eventual need for rigorous
justification of these conjectures is still emphasized.
The overall discussion of this Standard makes good use of specific
examples, both in the general discussion and in the specific descriptions
of the implementation at differing grade levels. The emphasis on using
coordinate geometry as a "bridge for linking the worlds of algebra and
geometry" (page 63, lines 3-4) falls right in line with one of our ARG's
recommendations for the treatment of geometry.
The subsections on transformations and spatial reasoning (pages 63-65) are
well written. In short, I really do not have any suggested changes for the
presentation of this Standard in Chapter 3.
Chapter 4: Standards for Grades Pre-K-2
The organization of these gradewise discussions is very good, with
specific bulleted descriptions of implementation items followed by
discussions that are loaded with examples. This organization should be
kept.
page 123, lines 23-24: It seems far-fetched to claim that students
are developing the concept of a number line when using colored connecting
cubes. I recommend deleting this example, and instead bringing up the
modeling of number lines in the discussion of rulers on page 129.
Chapter 5: Standards for Grades 3-5
page 172, lines 6-11: This example is not well chosen, since the
exploration would not seem to require any assistance by computer. It can
be done very well visually.
page 172, line 30 through page 173, line 3: The emphasis on the
development of both two-and three-dimensional geometric intuition is good.
page 172, lines 4-12: Another very good feature is the emphasis on
correct use of standard mathematical terminology.
Chapter 6: Standards for Grades 6-8
page 227, lines 4-6: Students SHOULD engage in formal validations
using proof in high school. The word "may" should be changed to "should"
here.
page 228, line 26 through page 229, line 12: This is an excellent
exposition of the importance of exploration, conjecture, and justification
for this grade band. It should be kept as is. The same comment applies to
the discussion of the role of the Pythagorean theorem given on page 230,
lines 4-20.
page 230, line 23: The use of acronyms whose meanings are not
widely known outside the mathematics education community, such as MIRA that
appears here (about whose meaning I am clueless), should be avoided.
Chapter 7: Standards for Grades 9-12
page 294, line 15 through page 295, line 6: I am not happy with the
way this problem is stated, specifically, that the line segment is
"randomly divided into three lengths" and the supposition that "x and y
represent two of the three lengths." I suppose that this means something
such as the segment is "divided into three subsegments by two points chosen
at random along its length" and that "x and y represent the lengths of the
two noncentral subsegments," which then justifies the analysis given. An
alert student might (and should!) worry that some other interpretation
might be assigned to the notion of randomly dividing the segment into three
"lengths" and that the answer will then be different.
page 298, line 31: Here is another undefined acronym, ARISE.
STANDARD 4: Measurement
[David Kullman]
I like the overall approach to this standard, starting with "the process
of measuring" in grades Pre-K-2 (page 128, line 6) and eventually
characterizing measurement as "the process of assigning one or more numbers
to the properties of an object" (page 300, line 7).
[Henry Pollak]
In Standard 4, both overall and in the individual levels, there are
several items which seem to be delayed too long or missing. One is the
fact that in the context of measurement, 3 and 3.0 are not the same thing.
3 inches means that the actual length is between 2.5 and 3.5 inches; 3.0
means that it is between 2.95 and 3.05. I didn't see this anywhere in the
measurement standard; it might be in the number standards somewhere -- I
haven't read all of those. There is good discussion in various places
about measurement precision and errors (e.g. pages 177 and 236), but not of
the implication for notation. Next, the number of places to keep in a
computation is nicely done on page 304, but that's the Standard for grades
9-12! Shouldn't this come up sooner -- like grades 3-5? Third, there is
an issue which I didn't see mentioned at all, but which I think belongs
there. That is the implied accuracy of numbers in everyday speech. When
we say that A is 82% of B, this usually means that the computation gives a
number between 81.5 and 82.5. If we say 80%, it often means between 75 and
85; 50% often means that it's not close to either 0 or 100, and no more
than that. Another example of the same phenomenon: Conversions between
metric and English units when the original number is much rounded often
gives ridiculous-looking results in the newspapers.
Page 303, lines 7-15. The write-up makes no point of the fact that
the coefficient of log x on line 8 is 1.500 to three decimal places.
Historically, that was enormously significant - Kepler's Third Law! Does
the omission of this send a message that we want sent? Thoughts from
Standard 6 are found elsewhere in the discussion of Standard 4 - especially
in Grades 9 - 12. Why not here?
[Stephen Rodi]
It is indeed the better part of common sense to include, as the document
does, both metric and "customary" measurement systems in the curriculum
(page 67, lines 36-37).
I thought the sequencing of the measurement material from Pre-K through
Grade 12 was well laid out. In particular, I was impressed with the
frequent use of short examples or model problems to clarify ideas. I
thought this technique of exposition especially effective for teachers in
the lower grades (prior to Grade 9) who might wonder exactly what or what
level of sophistication was intended.
The emphasis on estimation and approximation in Grades 3 - 5 and again in
Grades 6 - 8 is excellent.
I suggest that the word "emerge" on page 178, line 34 (as in, formulas for
measuring perimeter, area and volume should "emerge" from student recording
of information and looking at patterns) may come back to haunt the
document. There is a lot of potential pedagogical misinterpretation in
that verb. Maybe something like, "In their work with measurement, students
should begin to recognize the standard formulas for....."
In Grades 6-8, the presentation of measurement had a very strong geometric
flavor, which I thought appropriate. As I read this material, the
following thought struck me. One way of resolving the dilemma "Should
algebra be studied in 8th grade?" would be to start the formal study of
algebra in 9th grade but to substantially beef up the study of geometry in
Grades 6-8 with some deductive geometry and a little informal algebra
embedded. This might better prepare students to deal with the abstract
symbolism of algebra which seems to cause so many students trouble these
days. In fact, from what I could tell, Principles was recommending a
course similar to this.
I agree with the statement directed to Grades 6-8 on page 232, line 21,
that "measurement should be emphasized throughout the school year, rather
than treated as a separate unit of study." However, I think at these grade
levels some specific instructional units might concentrate directly on
measurement as a transition from the intuitive, object-based experiences in
earlier grades to a more formal and abstract understanding . This should
not be overdone, but also should not be lost in a more "spread out"
instruction on measurement.
I would like to see a comment (similar to the one above on page 232, line
21) included in the material for Grades 9-12. Here it should have the
additional emphasis that in Grades 9-12 students are in science classes
where measurement is critical. Measurement ideas have to be drilled,
repeated, and "exampled" constantly with students so that they become
second nature.
I was surprised in the Grade 9-12 material to find very little (in fact, I
think, no) linkage between measurement in mathematics classes and in
science classes, even though the major example in this section was a
physics problem! This appeared inconsistent with the emphasis in the
Pre-K-2 and Grade 3-5 presentations of the importance of physical
experience in learning about measurement. It seemed the draft writers were
avoiding reference to the "real world" precisely when one got close to the
"real" study of the real world in science! Is the orientation for "all
students" affecting this presentation?
At the other extreme, the "log-log" example in the Grade 9-12 material
seemed overly sophisticated for the point being made in this expository
document. The document may need a more centrist example here.
I suggest eliminating the word "some" in line 21, page 304. A goal of
"some understanding" is too low, even for "all" students. At the Grade
9-12 level, it is not too much to expect all students to have a "full"
understanding of "basic formulas for surface area and volume."
As a final comment, I observe that my biggest trouble in teaching calculus
in college, especially to business and social science students, but even to
science students, is their almost non-existent sense of unit and
measurement. Even more important than coming to me with algebra skills
(which they do not) would be their arrival with a clear idea of how rates
are measured and what such measurements mean: dollars per year, people per
day, milliliters per minute. The actual meaning of the derivative, as
opposed to grinding out numeric answers, remains an eternal mystery to them
because they do not understand these basic measurement concepts and how to
express them. Their level of ignorance reveals itself daily when asked to
put a measurement label on a numeric answer.
[Bob Megginson]
Chapter 3: General Discussion of the Standard
This discussion lays out well the general intent of this standard. The
progression through the grades seems reasonable. Appropriate emphasis is
given to connections with other areas of mathematics, such as geometric
notions of congruence and similarity (page 68, lines 6-17) and the uses of
under- and overestimation in calculus (page 68, line 36 through page 69,
line 5).
page 69, lines 17-32: I agree strongly with the statement that
"Strong connections need to be made between the formula and the actual
object." However, I am worried about the example involving the formula for
the area of a circle. Using this plausibility argument to convey intuition
about the area of a circle (1) ultimately relies on another geometric
formula for which the students may not have any better intuition than for
the area formula, namely, the formula for the circumference of a circle;
(2) does not convey the important point that the real idea behind the
formula is that the areas of similar figures are in proportion to the
squares of corresponding linear dimensions; and (3) does not in any case
seem intuitive enough to come to mind quickly when students are using the
formula. This plausibility argument can be shown to students as a way to
relate the constants of proportionality in the formulas for the
circumference and area of a circle, but the primary intuition for the
formulas should come from their relationship to standard facts about
proportionality for similar figures.
Chapter 4: Standards for Grades Pre-K-2
page 129: The use of rulers is mentioned several times. This is an
appropriate place to discuss the development of the notion of a number line
in the minds of students in this grade band, rather than through the
example on page 123, lines 23-24, that uses colored connecting cubes.
Chapter 5: Standards for Grades 3-5
This section is particularly well stocked with examples to illustrate the
ideas.
page 179, lines 9-15: Although the instructions for the ball drop
experiment say to drop the balls from different heights, the table data
show that all balls were dropped from the same height, 100 cm. This minor
discrepancy should be eliminated.
page 179, line 21 through page 180, line 6: It is not clear that
the students will see that these measurements, such as the amount of water
consumed daily at the school water fountain, are being "carried out for a
purpose." Some of the examples should be replaced by ones for which the
real-world need is more apparent.
Chapter 6: Standards for Grades 6-8
page 233, lines 25-26: It is stated here that "there is no need for
students to memorize metric and customary measurement conversion
equivalencies," but on page 67, lines 39-40, it says that "Students will
find it helpful to know a few English-metric equivalents." I would
strongly urge sticking with the original statement from page 67. It really
is helpful for students to know, for example, that there are 2.54
centimeters in one inch.
Chapter 7: Standards for Grades 9-12
This presentation seems fine. I have no suggestions to make.
STANDARD 5: Data Analysis, Statistics, and Probability
For more general concerns about the impact of adding statistics to the
mathematics program, see earlier comments by Henry Alder and Stephen Rodi
in CONCERN #5 of our main report.
[Stephen Rodi]
Perhaps more discussion could occur in the Pre-K-2 section on using play as
a source of informal introduction to these ideas. As the document only
partly recognizes, in these grades children are very young and
intellectually very non-abstract. Inclusion of these topics in the
curriculum, it seems to me, would have to be very informal at this
level.
For Grades 3-5, I thought some of the goals (e.g., page 182, line 1-7) a
bit sophisticated, especially for Grades 3 and 4. The level of abstraction
of the actual classroom presentation would make a difference. But, if
presentation is as important an issue as I think it will be, Principles
should give more guidance, rather than lumping all of these grades
together. My parenting experience tells me that third graders and fifth
graders are very different creatures as regards readiness to deal with some
of these ideas.
I very much like the statement in line 28, page 237: "Students' work with
data analysis and statistics in grades 6 -8 draws on and integrates their
knowledge of ratios, fractions, decimals, percent, graphs, and
measurement." This sort of integration, in my opinion, is exactly what
should be occurring in the middle school grades, rather than a rush to
algebra for all students. As I have said above, I think geometry should be
the other main support of the middle school years.
I don't know what is intended by the statement on page 310, line 14 that
"probability is counter-intuitive for most people." I find the basic idea
of probability very intuitive for most students. In a world of lottery pay
off, Las Vegas vacations, and weather reports, the intuitive idea of
measuring "chance" is one of the few ideas I can depend on students having
when they show up in class. The formalizing of that intuition is what
gives trouble.
The breadth, depth, and specialization of the Grade 9-12 material reminds
me that a vast part of the secondary school teacher corps will be unable to
deal with this material in an insightful way, if it is dispersed throughout
four years in an integrated mathematics curriculum. Will this stark
reality in effect move these topics into separate courses taught by
specialists and effectively undermine the goal of all students seeing these
topics? If not, how will the ability of the teacher corps to teach these
topics be managed?
[Henry Pollak]
In the overall discussion of probability, conditional probability is
mentioned in the Chapter 3 overview (page 75, line 28). The experimental
evidence is certainly that this is difficult for students, and the only
place it occurs is in the 9-12 standard on page 310. At this point, one
might mention that it is a good application of rational functions. All the
way through, it might be worth saying that probability is not only an
excellent application of rational numbers, but can also be used to motivate
a variety of operations on rational numbers.
In the discussion of data analysis at all levels, there is frequent
mention of students taking their own data and then analyzing them. I am
delighted with that, but I notice that there is never any mention of data
presented in the textbook which students then work with. It seems to me
there is a place for this also.
Page 183, Figure 5.14. The numbers on the abscissa are meant to
represent intervals, not coordinate points, but that isn't clear.
Page 240, Figure 6.8. Brand 1 has two entries of 1 pepperoni each
in the bar graph, but these have disappeared from the box-and-whiskers
plot, which has 2 pepperoni as the minimum value. Why? Are they outliers
more so than the 13's? There is more than one accepted definition of
whiskers -- which are you using?
Page 309, Figure 7.18. People might see a logistic curve from 1790
to 1940, which then got a new "kicker" by the time 1950 came around.
Should something be said about this possibility?
STANDARD 6: Problem Solving
[Henry Pollak]
Page 136, lines 18 - 20. I am sorry, but I don't understand that
sentence at all.
Page 187, lines 23 - 29. Changing the fractions into decimals and
then comparing is not explicitly listed as a strategy. Didn't anyone try
this, for example on a calculator? Some people might take the omission as
a judgment.
Page 189, line 27 through page 190. There is no mention of handing
out 8 brownies, one to each person, and only dividing the 9th. Why not?
Again, some people might read something into this omission.
Page 244, up to line 21. The statement of that problem does not
require the "figure" to be connected, only that each square must have at
least one edge-adjacent neighbor. Is the union of two disjoint rectangles,
1x4 and 2x5, considered legal? Do you expect that question to be raised?
Is part of the learning what the problem does NOT say?
STANDARD 7: Reasoning and Proof
[David Kullman]
For each grade band, two common questions are addressed. (1) What does
reasoning (or reasoning and proof) look like in these grades? and (2) What
is the teacher's role in developing reasoning and proof? I think this is a
useful way to consider the standard.
In Chapter 5, the question, "What do students learn about mathematical
reasoning in grades 3-5?" seems redundant and should be subsumed under
question 1.
On the other hand, in Chapter 7 the question, "How does technology affect
the role of reasoning and proof in grades 9-12?" is well put. However, I
do not believe that it is adequately answered. In particular, I would like
to see a stronger, more direct statement to the effect that, while one
counterexample is enough to show that a general assertion is false, the
truth of such an assertion in several (or even many) cases does not allow
the conclusion that it is true in all cases.
I was disappointed that nowhere, in the discussion of reasoning and proof
for grades 9-12, is the phrase "deductive reasoning" used. There is also
no mention of the principle of mathematical induction nor of a deductive
system. (The latter IS included as a Focus Area in the 9-12 Geometry
standard.)
[Henry Alder]
I think Standards 7 (reasoning) is very well done. I like the early
introduction of mathematical reasoning, particularly stressing it in the
middle school grades, and its strong emphasis in the high school grades.
This is something I know is badly needed. I teach only upper division
mathematics courses at the present time, but I observe even at that level
how much the students' mathematical reasoning abilities have declined,
especially in the last few years. Questions are raised by students on
simple logic which I had never encountered until two or three years ago.
My criticisms of the treatment of this Standard are minor and are equally
applicable to other parts of the Draft such as:
- The use of meaningless trendy terms such as "powerful reasoning"
(see page 139, line 21).
- Statements which are unclear such as (page 191, lines 13 and 14): "A
focus in these grades (3-5) is for students to create mathematical ideas
themselves and to articulate, examine, and evaluate these ideas". It is
not clear to me how a third grader would do this.
- Use appropriate mathematical terminology wherever possible, for
example, "proof" instead of "convincing mathematical argument" (see page
316, line 13).
[Susanna Epp]
By and large, the discussion of reasoning and proof in the grade-band
sections was disappointing. If students are to succeed in proving and
disproving basic statements about numbers and geometry in high school, the
discussion in the preceding sections of PSSM should indicate how the
thought processes necessary to achieve this goal are to be built up over
the years. What experiences will lead students to understand that a few
examples do not prove a general statement but that one counterexample will
disprove it, that the truth of "if A then B" implies the truth of "if not B
then not A" but not necessarily of "if B then A," and that to show a
statement P is true, it suffices to show that not P is false? More
generally, how will students learn to distinguish valid from invalid
reasoning? The draft PSSM hardly addresses these crucial issues at all.
In particular, there are no references to the use of logical puzzles, which
are effective in giving students a sense both for chains of inference and
for proof by contradiction. Nor is the concept of "generic example"
discussed, where one works through an example illustrating a general
property with one set of numbers and then points out how each step in the
solution would be equally valid if any other numbers were substituted.
Generic examples provide a transitional stage in the development of the
concept of proof by making it possible to engage in deductive reasoning
about "any" things with students not yet mature enough to deal with
sophisticated mathematical notation. For example, a proof that the decimal
representation of any rational number is terminating or repeating would
involve extensive use of subscripted variables but the idea can be
effectively conveyed through discussion of a generic example.
In general, these grade-band sections do not go far enough in suggesting
ways that teachers can help students learn to distinguish an argument
justifying a statement from evidence establishing its plausibility.
Justification might be sketchy, contain gaps, and neglect special cases,
but suitably enlarged, a justification for a statement should be capable of
being expanded into an actual proof. On the other hand, noticing a pattern
in a certain finite set of data or observing an analogy between two
mathematical structures merely establishes plausibility for a general
property by providing supporting evidence that it might hold. But such
evidence does not constitute valid justification that the property holds in
general.
STANDARD 10: Representation
[Stephen Rodi]
I was delighted to read the material in pages 94-100. The nexus between
mathematics and language has been under-used in teacher preparation and in
instruction. Students, and probably too many of their teachers, see
mathematics as a great puzzle to which one needs to learn the tricks and
keys. They don't appreciate mathematics as a way of expressing knowledge
and understanding, in part because they do not understand language either.
Pages 94-100 address this phenomenon head-on. It should be a core unit in
every university mathematics education curriculum.
The discussion of "idiosyncratic" representations (page 96, line 14-28)
offers an area wherein the Principles document opens itself for criticism
and wherein it should choose its words carefully. I would suggest one
change in lines 25-26. Drop the phrase "when appropriate" at the end of
the sentence "teachers can build bridges from students' personal
representations to more conventional ones, when appropriate." There are
those who believe such a bridge always is appropriate, but by omitting the
phrase the issue is left more open for individual interpretation.
I found the "level" of material discussed under this Standard for Grades
3-5 distinctly less sophisticated than the Grades 3-5 material for Standard
Five. This only re-enforced my instinct, alluded to above, that the
presentation (or perhaps actual level) of the Grade 3-5 material for
Standard Five needs to be re-visited.
The "algebra paragraph" in this "Representation" Standard for Grades 6-8
(page 265, lines 3 -12) seems pitched at a more sophisticated level than
what is proposed for algebra under Standard Two (page 222, line 1-10) for
the same grade level.
On page 267, line 25, "relatively large scale, motivating, and significant
problems" are proposed as "important." I suggest omitting the word
"relatively." I also note that some people (at least me) have an
instinctually negative reaction to what I call "semi-emotive" descriptive
words in mathematics education documents like "powerful" mathematics or
"meaningful" mathematics or "robust" understanding (page 268, line 4). (My
dictionary gives the fifth definition of "robust" as "marked by fullness or
richness" and applies it only to wine.) Perhaps three such adjectives in
the same sentence on page 267 is overkill. Finally, my question again
arises on how the rest of the curriculum will be carried out while such
"relatively large" problems are being solved? Teachers and others will
need direction on this.
The issue of idiosyncratic representations arises again on page 268, lines
6-7. I would suggest that the mandate given there that "teachers need to
be careful about trying to move students too quickly towards conventional
representations" needs discussion and perhaps re-phrasing.
In a similar vain, I would recommend omitting the word "eventually" in the
sentence (page 268, line 20) "Eventually students must learn to use
conventional notation so that they can communicate effectively with
others." "Eventually" sounds like this learning could be put off for an
awfully long time!
I also suggest that conventional notation does more for the student than
allow communication with others. Notations provides the very
epistemological "words" and concepts needed for a fuller understanding than
the student's home-made "representational vocabulary" allows. In this
light, one should be moving students toward conventional representations
more, rather than less, rapidly. Much lack of understanding can be
disguised in home-made representation.
The caveats (page 268, line 38-44) on testing student understanding of
personal representational presentations to verify if these reflect real
understanding are excellent. Such "testing" goes on daily in my business
calculus classes, long after students leave grade six!
I applaud the sentence of page 330, lines 19-21: "As they progress through
high school, students must continually develop their ability to
meaningfully interpret and use conventional, and increasingly abstract,
forms of representation fluently and flexibly."
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MAA Online is edited by Fernando Q. Gouvêa
(fqgouvea@colby.edu).