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Alexander Givental's avatar

Improving instruction one school (your local one) at a time is a great idea.

Early exposure to programming in connection with math ("write a C code for the Euclidean algorithm") is a great idea - too bad these days the task can be outsourced to an AI.

As about the rest, let me sketch an alternative picture.

1. Any revolutionary reform in education ends in a disaster (Examples: "New Math" of the 60-ies, "Fuzzy Math" in the 90-ies). The reason is: education = passing culture from one generation to another, while any reform makes teachers unable to teach and parents unable to help. Only gradual evolution of curriculum can be successful.

2. Totalitarian countries (where individuals exists for the benefits of the society, and not the other way around) have stronger math curricula (the society needs engineers) than democratic ones - where it is easy to make an argument that any particular item should not be taught "because very few people use it in real life". The proposal to replace "pre-calculus" (which is the only common-sense math in the US curriculum) with something "more useful" (such as probability and linear algebra) is, I am afraid, of this nature.

3. Those who think that math of early grades is "easy" and there is not much to learn there are gravely mistaken - read the book "Arithmetic for Parents" by Ron Aharoni of Technion.

4. Problem in the US math education begin in elementary school (by grade 2 former English majors successfully pass their hatred for the subject to their students). Even the excellent (grade 1-6) math curriculum from Singapore turns in the US soil in the absurd of solving 2-step arithmetic problems by labeling "bar diagrams" following an 8-step plan devised by devilish US educators (if you don't believe this, check "Signapore math" in youtube).

5. The mere discussion of how much should be memorized in math indicates the problem: in Russia, kids who prefer math to history say that they like math because "if you understand it, you don't need to memorize anything". And they are right!

6. "Calculus" = "Mathematical Analysis without proofs". It better not be taught at all. Especially in high school, because many will have to spend even more time with it when they retake it in college.

7. The main grade-school level math subject which, if taught properly, teaches theoretical understanding and creative thinking is geometry. As examples for the readers of this post, enjoy the following three math challenges: Using straightedge and compass, construct a triangle given (a) its three medians, (b) its three altitudes, (c) its altitude, median, and the angle bisector drawn from the same vertex.

8. If any curriculum change can be beneficial in the US landscape, it should be replacing the current "consecutive" curriculum structure (algebra-1 - geometry - trigonometry - algebra-2 - precalculus - calculus) with a "concurrent" one, where geometry is taught in parallel with everything else in a span of several years.

Finally, let me comment on math per se: the Pythagorean Theorem. Its proof illustrated in this post (apparently due to Martin Gardner) is indeed the most popular one, but just as most of the other 300+ proofs it is misleading about the nature of the theorem. It is presented as a clever way of cutting-and-tiling geometric shapes, while the theorem is actually about similarity. In the book 5 of his "Elements", Euclid revisits the Pythagorean Theorem (first proved in book 1) and generalizes it this way:

Suppose three figures of the same but arbitrary shape (not necessarily squares) are bult on the sides of a right triangle. Then the areas of the two figures built on the legs add up to the area of the figure built on the hypothenuse.

Since the shapes are arbitrary, no cut-and-tile argument would help. On the other hand, this statement for any one shape (e.g. squares) will imply it for any other shape - for proportionality reasons.

So, why take squares? The altitude dropped from the vertex of the right triangle to its hypotenuse DIVIDES the triangle into two, of the same shape as (i.e. similar to) the whole triangle and built on its legs (as their hypothenuses). That's it: the area of the whole triangle is the sum of the areas of these two parts.

If this exposition sounds too terse, check my article https://sumizdat.com/homepage/papers/eu.pdf - it also contains a Kindergarten-level proof of the standard Pythagorean Theorem which turns out to be about the three similar houses built by the Three Little Pigs.

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Coel Hellier's avatar

“Rather, it suggests cultural and class influences that act like genetic factors even if they are wholly environmental.”

At some point America will need to stop studiously ignoring the possibility of genetic factors themselves.

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