A multiple baseline design across participants was used to evaluate the effectiveness of a file box system plus self-monitoring on the organizational skills of four fourth and fifth grade students with high functioning autism (HFA) and Asperger's Syndrome (AS). Instruction took place in general education classrooms and consisted of teaching students to arrange academic materials (worksheets, note pages, study guides etc.) in a portable file box with hanging folders. Students were also taught to self-monitor their accuracy. The percentage of correctly filed items and the number of seconds it took students' to retrieve requested items were the dependent variables assessed across conditions. Results showed that the percentage of correctly filed items increased and the number of seconds required to locate specific items decreased with the use of the file system box. These findings demonstrate how a simple noninvasive and affordable classroom modification can improve performance of children with HFA and AS in general education classrooms. (Contains 1 table and 3 figures.)