Adams: My math-and-physics-teacher husband knew that if our daughter didn't take geometry in 9th grade, she'd never get to calculus. He was right.

It’s surprisingly difficult to prove one of the most basic properties of a number: whether it can be written as a fraction. A ...

Third grade was a long time ago, and many of us have forgotten even the most basic of principles. Fortunately, they’re pretty ...

According to statistics that must be true or I wouldn’t have made them up, 87% of grandfathers couldn’t pass a third-grade ...