An elementary-school math teacher silently paces his classroom in a pin-striped stockbroker shirt, his mouth full of braces. All around him, tiny students with pencils in hand struggle over puzzles at ...

Brain teasers are an excellent way to keep your mind sharp and engage your problem-solving skills. Ranging from simple to complex, these puzzles offer a fun yet challenging way to give your brain a ...

Two missiles speed directly toward each other, one at 9,000 miles per hour and the other at 21,000 miles per hour. They start 1,317 miles apart. Without using pencil and paper, calculate how far apart ...