I memorized a bunch of these for high school math competitions. You got very familiar with squares up to 100, prime numbers up to 100, converting fractions and

I memorized a bunch of these for high school math competitions. You got very familiar with squares up to 100, prime numbers up to 100, converting fractions and repeating decimals. A sample test from back in the day: http://www.texasmath.org/DL/NS/NS9394.pdf http://www.texasmath.org/DL/NS/NS9394.pdf Of course, I've forgotten most of the tricks because they were so specific to the test.