Children in kindergarten and grades 2, 4, and 7, and a group of adults were asked to choose, from a series of paired pictures, which of each pair represented the situation described in a statement that contained an ambiguous negation. In all five sentence types represented, there was a gradual progression toward adult performance, but approximation of adult performance peaked at different ages. The forms "Some of the rabbits aren't in their cages" and "None of the rabbits are in their cages" peaked at grade 4, and the form "Not all of the rabbits are in their cages" at grade 7. The most striking result occurred in the category of quantifier negation ("All the rabbits aren't in their cages," read with the emphasis on "all"). Despite the tendency of children to pick up on intonation as an early grammatical device, this category produced by far the highest "error" rate: only 38% adult norm responses at K level, in a pattern that persists through grade 7. This type of sentence thus appears to repair with intonation a contradiction between the surface marker and the underlying scope of the negation, and the acquisition of this syntactic structure appears to be put off until a relatively late age. (JB)