Summary.100 boys and girls of 13+ years of age were given repeated trials on a simple musical theme. The performance on eight consecutive trials was related to performance on a battery of musical and other tests and the factors underlying performance were elicited. It was found that the task was complex and changed in complexity during the eight trials. The learning curve for a hypothetical performer was broken down into a series of other curves corresponding to the factors revealed in the earlier part of the study. It was found that these curves did not follow the overall learning curve although they behaved in a generally regular manner.