Every year, the countries competing in the International Mathematical Olympiad arrive with a booklet of their best, most ...

Teachers can use these questions to draw students out and get worthwhile formative assessment responses to guide instruction.

Mathematicians, are you ready? This second-grade math problem is a doozy—and it seems like no one can figure it out. (By the way, if you can solve this math puzzle, you’re probably a genius.) Angie ...