The addition and subtraction in this math puzzle game isn't tough at all. What is challenging is figuring out what blocks to combine to come up with zero in the final block. If you get stuck, just click the Video button on the main screen to see how to solve each level. Number block puzzle, math game, addition, subtraction, zero, problem solving, kids games, educational games, logic puzzle, number sense, mental math, strategy game, puzzle game, video hints, number combination, brain training