Teaching children with autism to ask questions about hidden objects.

We taught 2 4-year-old children with autism to ask questions of an adult who held a closed box with a toy inside. The treatment package (modeling, prompting, and reinforcement) was evaluated with a multiple baseline design across the three question forms during training, generalization, and follow-up evaluations. The first question form ("What's that?") produced the name of the hidden item. The second form ("Can I see it?") produced sight of it, and the third form ("Can I have it?") produced the item itself. Both children learned to ask questions about hidden objects.