Factual error: In the scene where Joe Clark and the Vice Principal go to the project buildings to see the young girl's mother, they walk down a short ramp to an apartment. Those project buildings are in Paterson,N.J. (where the story takes place), but walking down that ramp takes you to the boiler room, not an apartment. None of those buildings have apartments like that.
Factual error: Just after the opening credits, Thomas Sams is stuffed into a locker by two other boys, but a big kid like Sams would never fit into a real high school locker.