Refraction is an online puzzle game for teaching fractions. The game is not obviously a lesson in fractions, but requires knowledge of fractions to succeed. In Refraction, the player must partition lasers in order to power spaceships containing various animals who have gotten stuck in space, as shown in the picture. These animal spaceships all require different fractions of the lasers, and the player is given several pieces that split and bend the lasers to reach the animals and satisfy these requirements. These mechanics can be used to teach many important fraction concepts, such as equal partitioning, addition, multiplication, mixed numbers, improper fractions, and common denominators. The game itself is instrumented so that it records everything the player does, allowing teachers and researchers to analyze play data.