The author traces the history of the applicability to students of the Fourth Amendment, which defines search and seizure of person or property to be illegal without a valid search warrant supported by probable cause. Various court decisions have affirmed students' constitutional rights, but Louisiana is the only state that has held, in a decision, that the Fourth Amendment requirement of probable cause applies to school searches. School searches have been supported in courts on the grounds of the the doctrine of "in loco parentis," and many courts have adopted a reasonable suspicion standard alone. The purpose of the search and the nature and extent of police involvement are factors that courts consider in determining the applicable standard for the search. As a rule, however, courts have held that police involvement in the initiation of a search or the search itself requires the application of the probable cause standard. Court decisions reveal a pattern that increases the standard of reasonableness required on a continuum from the student's desk and locker to car, clothes, and person. Two cases of strip searches were invalidated. The appendix at the end of the chapter contains two sample forms--one a board of education policy statement about searches, the other a notice to students. (MLF)