Sound-augmented toys producing factual knowledge were thought to encourage incidental, playful learning in children with visual impairments (VIs). A group of 15 children with VIs and 22 sighted controls played with a sound-augmented savannah landscape and listened to an informative story in a counterbalanced order. Children's knowledge about savannah animals was assessed at baseline and after each condition in order to quantitatively compare knowledge gains between conditions. Results indicated that children with VIs gained more knowledge than sighted controls from playing with the sound-augmented toy. Furthermore, offering both the augmented toy and the informative story led to higher knowledge gains than a single medium, especially in children with VIs. Sound-augmented toys could therefore be a useful addition to the current curriculum in special education for children with VIs.