1. SYMBIOSIS Start by putting a counter (a coin, or other small object) on the top left and top right arrows. You want to move the counters to the bottom left and bottom right arrows. Do so by repeatedly moving one counter one space in the direction of the arrow underneath the other counter. The counters should never leave the grid. For example, the only starting move is to move the counter in the top left to the center arrow.

2. NUMBER SQUARES In each puzzle, put the digits from 1 to 9 (each used once) in the squares so that each number along the side of the puzzle is the sum of the digits in that row or column.

3. MATCHSTICKS Start with the number 36 made from 11 matchsticks, shown above. What is the largest number that you can make by moving 1, 2, 3, 4, or 5 matchsticks, leaving the rest in place? Each number must use all the matches and each digit must look like one of the 10 digits below. Don't get burnt!

4. HAIL TO THE CHIEFS Fit 16 of the 19 presidents listed into one of the grids.

5. Three Easy Pieces The shape above can be cut into 3 congruent pieces in 2 different ways. Find a shape that can be cut into 3 copies of either of the 2 shapes below. Pieces can be rotated or reflected.