Pete breaks up a fight and a student is injured.
This episode seems to be lost as it does not show up in reruns or on the DVD set that I own. I remember it from when I saw it when first broadcast, so I will go by my memory.
There is an obnoxious, irritating student in class who is played by Michael McGreevey. He was doing quite a bit of TV and film at this time. He was Kurt Russell's friend in Disney film The Computer Wore Tennis Shoes and also showed up in the sequels.
The jerk character gets into a fight with Bernie, Pete breaks it up and shoves the jerk into a locker, he hurts his arm and sues Pete.
There is scene where the jerk has a smug look on his face when he sees the trouble Pete is in.
I hope they find this episode somehow because I remember it being one of my favorites.