It's hard math for middle school.
If C. and I had worked our way through Art of Problem Solving's Competition Math for Middle School, neither of us would have gotten stuck on the factoring problem we both got stuck on:
r2 is a multiple of 24 and 10. What is the smallest value?Competition Math for Middle School, a book for mathematically gifted middle schoolers, explicitly teaches the answer to this question:
441, 256, and 576 ... are all perfect squares. If a number is a perfect square, each of the prime factors will have an even exponent in its prime factorization.Leafing through the two books, I am struck by the the amount of explicit, procedural teaching directed to mathematically gifted students. No one's asking them to figure these things out or to "problem solve." Instead, they're being directly told that all of the prime factors in a perfect square will have even exponents.
J. Batterson, p. 139
Ditto for the how many diagonals in an n-gon, a perennial favorite amongst SAT math writers these days, it seems.
correction: My wording above -- explicit, procedural teaching -- implies that these books teach procedures instead of concepts. That's not at all the case and isn't what I meant to convey.
What I meant to convey was the fact that gifted middle school students aren't being asked to figure out concepts for themselves; they're being explicitly told how the problems work, and why.