I’ve received multiple requests to blog about Paul Lockhart’s “A Mathematician’s Lament.” Lockhart is a math teacher who is fed up with elementary and high school math education. I haven’t blogged about Lockhart's piece primarily because I agree with most of what he has to say and also a lot of people have already talked about it. (See for example, Scott Aaronson’s insightful commentary.)

Lockhart’s thesis is that much of mathematics education is simply wrong. According to Lockhart, the vast majority of our math education before college is rote learning that does not convey what mathematics is about. Lockhart argues that much of what children do in high school would be the equivalent of painting by numbers if we translated it into art. Mathematics is far more about exploration and understanding than it is about rote memorization. Lockhart argues that, by failing to let children understand and explore, we are not even teaching them mathematics. Lockhart further argues against rote math education based on practicality i.e. that these are techniques children will need when they are older.

Lockhart makes many good points and I recommend that people read his piece. As someone who has worked for many summers with the PROMYS program which uses a method similar to that outlined by Lockhart, I have much sympathy for his viewpoint. However, there are three problems with his thesis.

First, Lockhart overemphasizes the willingness of students to do exploratory mathematics. Exploration is intrinsically difficult. Moreover, it is difficult to get people to do math exploration if they don’t want to. If one tries to get youngsters to explore and they can’t do it effectively , the result is that parents will do the “exploration” for them. I’m sure there are readers of this blog who remember their parents “helping” with art projects back in elementary school.

Second, Lockhart underemphasizes the actual importance of rote learning and drills in picking up basic mathematics. Students need to be able to add, subtract, divide and multiply. They need to be able to do these things quickly in real life. Moreover, they need to do them enough times that they develop an intuition for orders of magnitude and when answers look right or wrong. That requires drilling in arithmetic from a young age. Lockhart addresses this issue briefly, but his response is unsatisfactory.

Third, Lockhart’s choice of focus on specific aspects of the high school and elementary curriculum is poor. He is correct in his criticism of the large amounts of trig memorization that occur. But he is incorrect in his example of the quadratic formula. In order to have an intuitive understanding of parabolas and other curves of degree 2, you need to know the quadratic formula. Moreover, the formula comes up frequently enough in later math classes that not knowing it would be a serious barrier. Finally, there are some items that educated people just need to know. Understanding the quadratic formula is one of those things that educated people just need to know in the same way that you can’t be an educated citizen of the United States and not know who Abraham Lincoln was.

Despite these criticisms, Lockhart is essentially correct. There are many serious problems with how we teach math and Lockhart correctly identifies many of them. While the massive overhaul that he outlines may not be necessary, it would substantially help matters if children were exposed at a much earlier age to what mathematics actually is, a subtle and beautiful art.

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