Wh-questions represent one important step in the acquisition of children’s syntax which generally takes place within the first three years. Two syntactic operations which are related to the position of the pronoun and the position of the verb play an essential role in this process. In three studies it was examined if children acquiring German could distinguish grammatical and non-grammatical wh-questions before being able to produce wh-questions themselves. Furthermore children with typical and atypical language acquisition were compared in their ability to comprehend and correct wh-questions of different complexity (positive and negative wh-questions). The results indicate an early syntactic knowledge about wh-questions in language acquisition and support the hypothesis of continuity between children’s and adults speech. Children with typical and atypical language acquisition do not show any qualitative differences in their way to acquire wh-questions. Much rather the time point of acquisition is delayed. An effect of syntactic economy was found in both populations. Children seem to realize syntactic violations against the movement of the wh-element earlier than those against the movement of the verb.