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Mr. Milgram: I would like to start by
again thanking David Klein and Cal State Northridge for arranging and organizing this
wonderful opportunity to get together and compare ideas on the incredibly challenging
times ahead of us. Professor Wu brought up a number of critical points in his
discussion and one of them that he mentioned -- that this is a long term challenge -- is
particularly important.
I'd like to
fill in somewhat what the problem is here. First of all, "long term" has
generally been understood to be in the order of perhaps three years, and there seem to be
real expectations of being able to meet the standards in that time frame. But this
is very unrealistic!
A realistic
long term is maybe 15 years. If we are lucky, in 15 years the average student may get near
the standards if everything goes just right. In a shorter time than that, it is almost
inconceivable to believe that this will happen. California today ranks just about at the
bottom in the United States, in terms of the level of mathematical achievements of
students in K-12. The United States ranks near the bottom among all the developed
countries in the world in terms of math achievements of students. We have an incredibly
long way to go because you have to remember that the new California Mathematics Standards
were written to match the levels of the standards of the top achieving countries in the
world. Meeting these standards is a daunting challenge and we had better take it
seriously.
We now look at
the reasons we clearly needed new standards in mathematics. They can be subsumed in
three main areas.
REASONS FOR NEW
STANDARDS
- The increasing failure of the present system to produce
enough technically skilled graduates to meet national needs
- Curricular problems which leave more and more students
without the prerequisites needed for their majors, particularly in technical areas
- Lack of a clear understanding - on the part of teachers
and math educators - of the major goals of the mathematics component of K-12 education
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The next three slides explain a little bit
about how we see some of this so we cannot escape from these issues. The facts
quoted in these slides come from recent newspaper articles for the most part.
INDICATIONS OF FAILURES
- From 1990 to 1996 there has been a 5% decline in
high-tech degrees -- engineering, math, physics, computer science -- in this country and
the trend is continuing.
- Of the decreasing number of high-tech degrees awarded a
significant and growing proportion go to foreign nationals.
- At the doctorate level 45% of high-tech degrees were
granted to non-U.S. Citizens
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From 1990-96,
there's been a 5% decline in high-tech degrees overall in this country. And the trend is
continuing -- in fact, the trend is accelerating. Even though the number of
high-tech degrees is decreasing, it is vital to note that an ever increasing portion go to
foreign nationals. At the doctorate level, for example, 45% of high-tech degrees are
granted to non-U.S. Citizens and at Stanford, in the mathematics department, two
thirds of our graduate students are foreign-born. Even 10 years ago, less than half
were.
As a result of
this situation it has been impossible to fill all our technical jobs with United States
citizens. This is particularly true in Silicon Valley. To find qualified
people to fill these positions Congress was intensely lobbied by Silicon Valley, and
Congress was forced, much against their will, to provide 142,500 more visas for foreign
nationals to fill jobs in Silicon Valley. Currently it is estimated that the number
of foreign-born residents of Silicon Valley is about 25% of the population.
Among all the states as I said in the
beginning, California colleges showed the greatest decline in high tech degrees.
INDICATIONS OF FAILURES - II
- Last year Congress was forced to provide 142,500 more
visas for foreign nationals with high-tech skills
- Currently it is estimated that the number of foreign born
residents of Silicon Valley is about 25% of the population
- Among all states, California's colleges showed the
greatest decline in high-tech degrees awarded.
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So the first
point is that the system today is simply failing to produce enough technically qualified
graduates to meet national needs. The foremost problems and most dramatic declines are
here in California.
Curricular
problems are overwhelming here and leave more and more students without prerequisites
needed for developing and learning technical skills in college. When they come to us, even
at Stanford, more and more of them are just not able to become engineers and scientists,
even though this is their original intent. They just don't have the background any more.
It is a dramatic change.
Finally, and sadly, because I have the
utmost respect, and I think we all do, for the practicing teachers, the level of
understanding on the part of teachers and above all of math educators -- that is members
of the educational schools throughout the country -- that is required for teaching
mathematics in K-12 is just not there any more.
Look at the effect of this lack of
understanding on our students.
INDICATIONS OF FAILURES - III
- The percentage of entering students in the California
State University System who are place into remedial mathematics courses after taking the
ELM placement exam is about 88%
- Overall, well over 50% of entering students are placed
into remedial mathematics courses.
- The average level of the questions on the recent version
of the ELM is about grade level 6.9 according to the new California Standards.
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This 88% is a
statistic that astounded me. And it is correct, differing from the failure rates commonly
reported (which are bad enough). The percentage of entering students in the California
State system who are placed into remedial mathematics courses after taking the ELM
placement exam is 88%. Let me emphasize this: 88% of those students taking the
exam fail it. Some of you may know a statistic of about 55% for the failure
rate. Unfortunately, this is calculated by counting the 40% of the entering
students who are not required to take the exam as having passed it.
These 40% are
counted as passing it probably so the statistic will look reasonable. I reiterate
that the actual statistic is 88% taking the ELM fail it, and it is not that hard an exam
overall. In any case, well over 50% of entering students in the California State
University system are placed into remedial math courses.
Those are some
of the reasons for our current problems. They stare at us. We can't avoid or deny them.
Now, I would like to give you an idea
of the real complexity of the problem and the consequent difficulty with trying to fix it.
On our first
slide the second problem with mathematics that I indicated is the lack of understanding of
curricular development on the part of math educators.
Curricular
development is a very complicated issue. As an illustration, I'm going to look at
one topic, long division, now. Long division is something that a lot of professional math
educators want to take out of curriculum. So let's just look at why it is in the
curriculum.
CURRICULAR PROBLEMS
- The recent fashion of not teaching material like long
division and factoring polynomials is based on claims that such skills are no longer
useful.
- This reflects a deep lack of understanding of the role of
mathematics in fields like science, engineering and economics.
- In mathematics many skills must be developed for many
years before they can be used effectively or before applications become available.
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First of all, I claim that taking -- even
asking to take it out of the curriculum -- shows a profound ignorance of the subject of
mathematics. The point is, in mathematics, many, many skills develop over an extended
period of time and are not really fully exploited until perhaps 10, 12, or even 15 years
after they've been introduced. Some skills begin to develop in the first or second
grade and they do not come to fruition or see their major applications until maybe the
second year of college. This happens a lot in mathematics and long division is one of the
key examples.
SOME SKILLS DIRECTLY
ASSOCIATED
WITH LONG
DIVISION
- Students cannot understand why rational numbers are
either terminating or (ultimately) repeating decimals without understanding long division.
- Long division is essential in learning to manipulate and
factor polynomials.
- Polynomial manipulation and factoring are skills critical
in calculus and linear algebra: partial fractions and canonical forms.
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So just to
start, understanding that decimals represent rational numbers if and only if they are
terminating or ultimately repeating -- a skill that was requested be put into the
standards by math educators -- cannot be understood without long division. It is
only in understanding of the process of taking the remainder in long division that you see
the periodicity or termination happen.
I regard the
repeating decimal standard as relatively minor, but some people seem to think it is
important. The next topic is critical and almost everyone thinks it's minor (Laughter).
Long division is essential to learning to manipulate polynomials. Without it, you simply
cannot factor polynomials.
So what, you
ask? Again, this is a question that doesn't come up until the third year in
college. At this point the skills that have come from long division through handling
polynomials become essential to things like partial fraction decomposition which is
important in calculus but finds its main applications in the study of systems of linear
differential equations, particularly in using Laplace transforms, which is the critical
construction in control theory. It is also essential in linear algebra for
understanding eigenvalues, eigenvectors, and ultimately, all of canonical form theory --
the chief underpinning of optimization and design in engineering, economics, and other
areas.
The previous slide indicated
what I call the static applications of long division. The next slide illustrates
some of the "dynamic" applications.
DYNAMIC SKILLS ASSOCIATED
TO LONG DIVISION
- The process of long division is one of successive
approximation, with the accuracy of the answer increasing by an order of magnitude at each
step.
- The skills associated with this process become more and
more fundamental as students advance.
- They include all infinite convergence processes, hence
all of calculus, as well as much of statistics and probability, to say nothing of
differential equations.
- Long division is the main application of the previously
learned skills of approximation.
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Long division
is the only process in the K - 12 mathematics curriculum in which approximation is really
essential. The process of long division is a process of repeatedly approximating and
improving your estimates by an order of magnitude at each step. There is no other point in
K - 12 mathematics where estimation comes in as clearly and precisely as this. But notice
that long division is also a continuous process of approximation, the answer keeps getting
more and more accurate and when the students learn how to do long division with decimals
they learn to carry the process to many decimal places. This leads naturally -- in a
well conceived curriculum -- to students understanding continuous processes, and
ultimately even continuous functions and power series. The development of these skills are
all contingent on a reasonable development of long division. I don't know of any
other or any better preparation for them.
What happens
when you take long division out of the curriculum? Unfortunately, from personal and recent
experience at Stanford, I can tell you exactly what happens. What I'm referring to here is
the experience of my students in a differential equations class in the fall of 1998.
The students in that course were the last students at Stanford taught using the Harvard
calculus. And I had a very difficult time teaching them the usual content of the
differential equations course because they could not handle basic polynomial
manipulations. Consequently, it was impossible for us to get to the depth
needed in both the subjects of Laplace transforms and eigenvalue methods required and
expected by the engineering school.
But what made
things worse was that the students knew full well what had happened to them and why, and
in a sense they were desperate. They were off schedule in 4th and 3rd years, taking
differential equations because they were having severe difficulties in their engineering
courses. It was a disaster. Moreover, it was very difficult for them to fill in the
gaps in their knowledge. It seems to take a considerable amount of time for the
requisite skills to develop.
APPLICATION OF THE SKILLS
ASSOCIATED TO LONG DIVISION
- The combination of these skills is used critically in
economics, engineering and the basic sciences via Laplace transforms and Fourier Series.
- Without a thorough grounding in these topics it is
impossible to do more than routine work in most areas of engineering, the most active
current areas of economics and generally, any area involving optimization.
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So you see the
problem. The problem is that the scope of things in mathematics is so long that an
ordinary second, third, fourth grade teacher is not equipped to make a judgment about
whether a subject is needed or not needed.
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SCOPE IN THE MATHEMATICS
CURRICULUM
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- The long division story illustrates one of the chief
problems with curricular development in mathematics. The period needed before a learned
skill can be fully utilized can be as long as eight to ten years.
- It takes real knowledge of mathematics as well as how it
is applied to make judgements regarding curricular content.
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I think the long division problem
illustrates the problem described on the slide above very well. And I put that dragon up
there advisedly.
EDUCATORS TELL US OF THE
NEED FOR CONCEPTUAL
UNDERSTANDING AND MATH
REASONING SKILLS IN OUR
STUDENTS
- These skills ARE critical in todays technological
society.
- What many math educators tell us represent examples and
exercises for developing these skills are NOT relevant and/or NOT correct.
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The first slide mentioned a third aspect
of the problem, which was the lack of knowledge of the subject on the part of math
educators. To make it clear, I'm talking about math educators and not teachers. Teachers
learn what they are told in the education schools and just hope that this background
prepares them sufficiently. They do the best they can and have the most demanding
job that I know of. As a group I believe they are the most dedicated people I know
of. But if you do not provide teachers with the proper tools, they can't do a proper job.
MATH EDUCATORS OFTEN
HAVE LIMITED KNOWLEDGE
OF MATHEMATICS
- For example, three of the 14 problems originally proposed
by the presidential commission on the eighth grade national mathematics text and/or the
"solutions" they gave were INCORRECT. This commission included many of the best
known math education experts in the country.
- The next slides discuss one of these problems.
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I just want to spend a few minutes, now,
looking at some of the problems that we have seen in the last few years when we -- as
professional mathematicians -- have looked at some of the things that math educators are
trying to tell the world is mathematics. I will concentrate on problems that these
people suggest for testing mathematical knowledge.
A PROBLEM FROM THE
NATIONAL EIGHTH GRADE
EXAM
We are given the following pattern of dots:
At each step more dots are added than were added at the
last step.
How many dots are there at the twentieth step?
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This is a problem from the original
proposed 8th grade national exam, produced by a presidential commission including most of
the best known math educators in the country. The problem appears to be simple and
every person I've asked, who I haven't warned to think hard and carefully about it, has
answered immediately, "Oh, it's of the form n times n plus 1, so you are looking at
the 20th stage, therefore the answer is 20 times 21."
But that's not
right. The words need to be read carefully.
The point is,
the words tell you the only thing you are actually given -- namely, that there are more
dots added at each stage than the previous stage. That's all you are given, and the
picture is just a picture.
ANALYSIS OF THE PROBLEM
- The answer given by the Presidential Commission on the
National Eighth Grade Exam was
20 X 21 = 420
- This is incorrect! The correct answer is that any number
of dots is possible as long as there are at least 267.
- As was pointed out, the Presidential Commission that
proposed this problem included many of the best known math educators in the country.
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ANALYSIS OF THE PROBLEM - II
- This can be seen by considering that you must add at
least seven dots to get to the fourth stage, eight to get to the fifth, nine to get to the
sixth, and so on, but, of course, you can always add more.
- So the formula for the number of dots at the nth stage with
n>2 becomes:
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Hmm? Actually that problem was about
as complicated as any problem I've seen at this level, and it was proposed for the 8th
grade national exam! When you read it carefully, it is a problem a 12th grade senior would
have trouble solving.
So what is the
moral here?
If you want to
learn mathematics, you must learn it precisely. Mathematics is precision and one of the
first objectives in teaching K - 12 mathematics is for students to learn precise habits of
thought.
The next slide
presents a problem that Wu is very fond of (Laughter). It can be found in many
sources, but in particular it was included as part of the original Mathematics Standards
Commission's proposed California Mathematics Standards.
A PROBLEM FROM THE
ORIGINAL STANDARDS
COMMISSION
STANDARDS
You have a friend in another third grade class and want
to determine which of your classrooms is bigger. How do you do it?
This problem is often proposed as an example
which shows that "there is no single correct answer" since you could use
perimeter or volume or area to measure size.
Of course, this is incorrect! |
The trouble is that bigger is not
precisely defined. And if every term is not precisely defined, your problem is not well
posed. So technically this is not a well-posed problem. Of course, we realize that is a
little technical. We have an idea that bigger has certain connotations -- but
unfortunately, a lot of them: perimeter, area, volume, and maybe even combinations of the
three such as 3A + 2.4P + 7V.
ANALYSIS OF THE
COMMISSION PROBLEM
The difficulty here is that bigger is not
precisely defined, and to do mathematics you generally have to know exactly what each term
means.
However, mathematics does provide for the situation where terms can have different
meanings. There is still a single "correct" answer. It consists of the set of
all answers.
But since bigger can mean anything, the set of answers is uncountably infinite, and this
problem is totally inappropriate for any but the most advanced high school students.
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You see, when you put in a linear
combination of the three, you get an uncountable number of possible definitions of bigger.
That's all right. Mathematics allows for this, as long as you can make some sense of the
problem. Mathematics says the correct answer to the problem is all
possible answers to the problem (Laughter). If you are going to take that problem at face
value, you have to give me an uncountable number of answers.
MORE DETAIL ON SOLUTIONS
Here is an example which illustrates the point that the
"answer" is a collection of "all solutions".
Consider the system of two equations in three unknowns:
2x + y + z = 1
x + 2y + z = 0
A solution is x = 1, y = 0, z = -1. The answer is
x = 1 + y
z = -1 - 3y |
So, what is the point? One of the most
important things, as I indicated, that students should learn in doing mathematics is
precise habits of thought. Suppose we start with a "real world problem", given,
as is typical for such problems, very imprecisely. We want students to be able to
break the problem apart into smaller problems, make sense of them, and solve them or
recognize that it is not possible to solve them with the information given. One of
the first things that mathematics should prepare student for is making the best possible
(rational) decisions when faced with real problems.
SUMMARY - I
One of the most important things that students should
learn from studying mathematics is precise thinking.
They should understand how to recognize when a problem is well-posed.
They should be able to decompose a possibly ill-posed problem into pieces which can be
made well-posed, and solve the individual sub-problems. |
Now, I don't for a minute want to minimize
the fact that students have to learn basic number skills, certainly they have to do that
too. And they have to learn things like statistics, I mean, this is critical in our world
today, and it is a wonderful thing that it is commonly taught today. It helps
prepare students to defend themselves from tricky claims and fake uses of
statistics. Students also have to learn how to survive in the monetary world. So a
key part of our request for changes when the State Board of Education asked some of
us at Stanford to help revise the California Math Standards was that compound interest be
put back into the 7th grade standards.
SUMMARY - II
They should also learn the basic mathematical skills
needed to survive in today's society.
These include basic number-sense
They also include skills needed to defend themselves from sharp practices, such as being
able to determine the real costs of borrowing on credit cards.
Additionally, they include being able to recognize illegitimate uses of statistics.
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I think everybody has the idea now. I have
many more problems here, all of which are incorrect and all of which are due to some of
the top math educators in the country. But I think you all get the idea of what the level
is here and what we are trying to deal with, so I think we can skip most of them.
But there is one more example that is worth noting (Laughter).
A PROBLEM FROM THE NEW
NCTM STANDARDS
The following is proposed as a Kindergarten problem:
How big is 100?
This suffers from exactly the same difficulty. I asked one of our best graduating seniors
this problem (he has a fellowship to study in Germany for next year and the year
afterwards will continue his graduate work at Harvard).
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This is from the current
new proposed version of the NCTM standards. "How big is 100?" It suffers from
every one of the flaws I mentioned before. But I loved the response from the student
above.
A PROBLEM FROM THE NEW
NCTM STANDARDS II
Without even a moment's hesitation he answered:
Oh, about as big as 100!
Indeed, any other answer would involve elements of perception and psychology, not
mathematics.
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Okay. I think probably I'll finish up now
and say again that it's a long process ahead. It is a serious, serious thing we are trying
to do. But I think it is something that we can do. It's just something we cannot treat
lightly and cannot treat in any way as a casual enterprise. For example if you hear
someone say something to the effect that "Oh, we're going to give the teachers the
Standards. We are going to say, now teach -- and it's over -- no problem," be very
suspicious.
IMPLEMENTING THE MATH
STANDARDS
- Problems
- California students rank at or near the bottom among all
the states in average mathematics competency
- Generally teachers in grades K-4 have little competence
in mathematics above their grade levels
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- Expectations
- We cannot solve these problems all at once
- Time is needed, and skills and competencies should be
introduced gradually.
- The new California Math Framework shows the most
important skills that must be learned first.
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It is a huge process -- of re-education on
everyone's part, it is a process we all have to contribute to and work on with full
attention. But I think there are grounds to hope that we can actually do it. And the one
thing that has the potential to help with this process is the Framework. The
Framework is something that Wu and I worked on with Janet and the Curriculum Commission,
and with many of the best people in many aspects of education throughout the
country. The Framework has been designed to ease our way into the teaching to the
Standards. It's something that I think we have to focus on a lot more in the next few
months as we try to figure out how to reach the levels needed.
I would like to
just say one word about one of the ways in which the new Framework can help.
IMPLEMENTING THE STANDARDS
- In first grade there are only five emphasis topics in
the Framework out of 30 total topics:
- Count, read and write whole numbers to 100
- Compare and order whole numbers to 100 using symbols for
less than, greater than or equal to
- Know the addition facts and corresponding subtraction
facts (sums to 20) and commit to memory
- Show the meaning of addition and subtraction
- Explain ways to get the next element in a repeating
pattern
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The critical thing about this is that the
Standards for first grade have about 30 basic topics. Well, those topics are, for the most
part, quite difficult at the first grade level and will take a great deal of time and
effort to teach properly. Fortunately, it turns out that only 5 or so of them are
essential. The Framework identifies the essential standards and makes your jobs as
teachers and your jobs as curriculum developers much easier because the textbooks in the
next textbook adoption will be focused on the emphasized topics, rather than the entire 30
topics in the Standards. So this will allow us to focus on just a few pieces and make your
job of reaching the levels needed a little simpler.
I think this is
where I'll stop (Applause).
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