When you think of Pornhub, you probably think of pornography, right? For good reason, the site is wall-to-wall porn. But one math teacher named Changshu noticed something was missing: math. “Since ...

The children puffed out their chests and mimicked drama teacher Melissa Richardson, rehearsing their big, booming “rhino voices.” “Giant steps, giant steps, big and bold!” the kindergartners yelled in ...