Most research on year-round education has focused on the effectiveness of year-round versus traditional-calendar schools. This paper presents findings of a study that examined student differences within a year-round elementary school by attendance cohorts (tracks). Specifically, the study sought to determine track differences in writing achievement. The data were collected from 430 students in grades 2-6 in a southern California elementary school, who were asked to respond to a writing prompt. Students' responses were analyzed by a general linear analysis of variance approach, with track, gender, and grade as the independent variables and writing score as the dependent variable. Findings indicate that students in track A performed significantly better than their counterparts in tracks B and C. Students in track A wrote better with increasing grade level, and students in tracks B and C did not show improvement with increasing grade level. Girls scored higher than boys, and older students received higher scores than did younger students. The higher level of student performance in track A, which featured a more traditional schedule, may have been associated with higher levels of parent interest in their children's placement and the tendency of students to remain in that track. Two tables are included. The appendix contains the scoring guide. (LMI)