In play, children often explore mathematical ideas that are vital for future learning. Children's play also reveals gender differences in both colour and toy preferences. The authors examined how gender-related colour preferences of 5-year-olds are related to preferences for math-specific games/toys and gendered beliefs about math. Spanish preschoolers (N = 143) completed a self-report measure of gendered beliefs about math. Children then indicated their favourite colour and were given five math-specific games/toys in that colour. Play times for each game/toy were recorded. Three findings emerged. First, girls preferred games/toys of particular colours (pink/purple) that differed from boys' preferences (blue/red). Second, play time with math games/toys did not differ between girls and boys. Third, 5-year-olds of both genders thought that girls liked math more than boys did. This is the youngest age at which these gendered beliefs about math have been shown, and suggests new theorizing about stereotypes, gender, and math. (author abstract)