Discrimination of question-asking is a critical conversational skill with considerable practical importance. Children with autism spectrum disorders (ASD) must be taught this skill to become competent communicators and function in everyday communicative situations. In previous question-asking literature, researchers have focused on teaching wh-questions in isolation. This study is an extension of previous research and conducted to investigate the ability of three preschool children with ASD to learn and discriminate when to use the two wh-questions, "What's that?" and "Where is it?" Results are interpreted to conclude that all three children learned to ask and discriminate between the questions within 6 to 16 instructional sessions, and learned novel vocabulary after asking "What's that?" This study supports using a prompting procedure for teaching these two wh-questions, and the importance of identifying individualized establishing operations to increase attending behavior, as well as conducting detailed prerequisite skill assessments to maximize learning of wh-questions.