Together, Ethan and I worked on a puzzle called One Tough Puzzle. This puzzle only has nine pieces but over 300,000 wrong ways to assemble them and only one right way. It is a great brainteaser, fostering problem solving, memory and other important learning skills. Ethan was also introduced to the game of Sudoku, which is a logic-based, combinatorial number-placement puzzle. We started with an easy puzzle with the numbers 1-4 but quickly moved to a 1-6 puzzle.