Variability is important to learning; however, whether itsupports or hinders language acquisition is unclear. 3D objectstudies suggest that children learn words better when targetobjects vary, however storybook studies indicate thatcontextual variability impairs learning. We tested a dynamicsystems account in which background variability should boostlearning by speeding the emergence of new behaviors. Twogroups of two-year-old children saw arrays of one novel andtwo known objects on a screen, and heard a novel or knownlabel. Stimuli were identical across conditions, with theexception that in the constant condition objects appeared on awhite background, and in the variable condition backgroundswere colored. Only children in the variable condition showedevidence of word learning, suggesting that extraneousvariability supports learning by decontextualizingrepresentations, and indicating that adding low-level entropyto the developmental system can trigger a change in behavior.