The absenteeism of 252 mainstreamed learning disabled (LD) elementary and high school students was examined over 4 consecutive years for elementary Ss and 3 1/2 years for secondary Ss. Orthogonal polynomial analysis was used to find the relationship between absenteeism and time as measured in school semesters. In general, analyses indicated the following findings: the absenteeism of secondary LD Ss generally increased across semesters, although the rate was less for Ss dismissed from Plan A (resource room program) than for those still in Plan A; the absenteeism of low-absentee elementary LD Ss showed only a small increase across semesters, and absenteeism was virtually independent of enrollment status in Plan A; and the absenteeism of high-absentee elementary LD Ss still in Plan A increased across semesters, but the absenteeism of high-absentee elementary students dismissed from Plan A decreased after the introduction of Plan A. Differences between projected average percent absent and actual percent absent showed that dismissed high-absentee elementary Ss attended more school after Plan A than would have been expected. (CL)