Is 800 Years Old Enough?
Class Notes links to a post by Kevin Horner about the math wars in Columbia Public Schools. He includes a YouTube video that criticizes Everyday Math for, among other things, teaching the lattice multiplication method. Horner writes:
The methodologies of traditional mathematics remain the most efficient algorithms for solving mathematical problems. Advanced math and science are based on these very methods.
This is a great example of why we shouldn’t just say "No new math." Horner is assuming that the way he learned to multiply is the "traditional" and "most efficient" way. But as you can learn from a little research on Wikipedia, lattice multiplication has been around since 1202. It’s hard to be more traditional than that. Furthermore, lattice multiplication is algorithmically equivalent to long multiplication. That’s a mathy way of saying that you’re doing exactly the same thing and you’ll get exactly the same answer. Lattice multiplication is not a less efficient algorithm than long multiplication; it’s the same algorithm, written out in a way that looks different. (And in a way that might be easier to understand for some students.)
So if a method that was invented around the year 1200 is too new, how are kids supposed to learn math? With only the most ancient Chinese abacuses?
Parents should be able to choose new math even if just for the simple reason that we can’t agree on which kinds of math are really "new."