Massacre at Central High

Massacre at Central High is a 1976 American thriller film directed by Rene Daalder and starring Derrel Maury, Kimberly Beck, Robert Carradine, and Andrew Stevens. The plot follows a series of revenge killings at a fictional American high school, after which the oppressed students take on the role of their bully oppressors. Despite its title, it is not a slasher film but an unusual blend of political allegory, social commentary, and low-budget exploitation; with the exception of the final sequence, no "adult" characters are seen.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.

Poster © the film's rights holders.