This study investigated the differences in academic achievement of regular education students in noninclusion classrooms and of same-grade students in special education inclusion programs, to assess the impact on regular education achievement of inclusion programs in a particular elementary school. All subjects were second, third, or fourth grade regular education students attending Bates Elementary School in Dexter (Michigan) during the 1989-91 school years. Each classroom was ranked as inclusive, noninclusive, or unacceptable for use in either sample. The results showed that the noninclusion regular education students did not exceed the academic growth of their counterparts who participated in inclusion programs on either reading or mathematics incremental change measures. Under the circumstances described for inclusion classrooms, regular education students' academic achievement was not negatively affected. The varying levels of means among the three grade levels could result from factors other than the treatment experienced by each group. Results suggest that concern for regular education students' academic progress should not deter educators from initiating special education full-inclusion programs. Contains 49 references. (AP)