What's the Difference? - Math Puzzle

Whats the Difference is a fun and challenging math puzzle. The object is to arrange numbers on a pattern so that the number between any two other numbers is the difference. For example, if 19 and 12 are on the same line, the difference is 7. The puzzle helps students learn about absolute value. Puzzles are randomly generated and so students will probably get a unique experience every time they try to solve the puzzle. The puzzle is fun for players of all ages, but perhaps most appropriate for upper elementary and middle school students.