ASD is diagnosed by perseverative behaviors and social deficits. While ASD children’s selective interest in the physical world may lead to more extensive exploration (and learning) of physical objects, they may learn less due to their perseverative behavior. How is exploration affected in children with ASD? We quantified exploration and discovery as children with ASD (N=35, M=8.5 yrs) and their controls (N=35, age, IQ matched) explored a novel toy with hidden functions. ASD children showed more perseveration than controls on every measure, and the diversity of their actions was negatively correlated with severity of autism. Furthermore, ASD children discovered less hidden functions than controls. While the control group showed a marked decrease in perseveration with age, ASD group showed a heightened level of perseveration independent of age. These data suggest that children with ASD show marked difference in their exploration of the physical environment, and this difference has real consequences for learning and discovery.