Educational board games are a promising teaching method due to their low cost, playful, exploratory, and engaging nature. By drawing on analogical research, we created a game whose structure of spatial relationships mirrored the structure of rational numbers. We expected that children playing this game would improve their knowledge of fractions. We conducted a school intervention with an active control group and pretest-posttest assessments to evaluate our board game. Playing this game promoted the learning of fractions, even after controlling for nonverbal cognitive abilities. This low-cost educational game might help reduce the knowledge gap that separates less and more affluent children.