Children Act, is a mainstreaming law and that its sole objective is wholesale return of mildly handicapped school-age students to the regular classroom. In point of fact, mainstreaming is not the law of the land-not for school-age children and particularly not for preschoolers. Rather, PL 94-142 requires only that children be educated in the least restrictive environment.The word mainstreaming does not even appear in the law. PL 94-142 does encourage preschool education through an incentive grant program, but it does not require that all handicapped children, birth to compulsory school age, receive a free, public education.