The notion that children over age 5 have acquired a conjunction once they have used it appropriately once or a specified number of times is challenged with data from a study of the narrative discourse of school age children. In the study, 26 adults and 71 children aged 4 to 11 were asked to tell a story about three sets of story pictures. Analysis of the resulting narratives indicated a clear increase in the frequency of subordinate conjunctions with age, with subjects under 7 using only "when" and "because," conjunctions already present in the speech of toddlers. In addition, it was found that children's use of conjunctions, particularly temporal ones, differed from the adults'. Some new insights derived from the results include: (1) the adult use of "when" to highlight contingency rather than co-temporal or sequential events; (2) certain constraints on the positional freedom of "when" clauses; (3) the relationship among "when" and the other temporal conjunctions, "while" and "as;" and (4) the rarity of "because" clauses. Further analysis of the data reveals more detailed information. A number of explanations are offered for these results, including the difference between ordinary conversation and narrative discourse, the need to revise previous notions of acquisition as an all-or-none phenomenon to reflect contextual learning, the complexity of the structures concerned, and the effects of the transition to literacy on the number and kind of subordinate devices found in children's language. (MSE)