When Ned's father prefers spending time with Homer, Ned ends up punching Homer in the eye; Miss Hoover is undergoing a bout of severe depression, and Lisa can't figure out why the substitute teacher doesn't like her.
Flanders becomes jealous when his laid-back parents start to prefer Homer's company over his and he faces unbearable guilt after punching Homer in the eye, as he desperately tries to reconcile with him.
Lisa's new substitute teacher, Ms. Cantwell, doesn't take a liking to the young know-it-all and bullies her with bad grades.
Meanwhile Ned is trying to negotiate with Homer and he punches Homer again in front of everyone. Marge is shocked at this and so is the townspeople. When trying to be the cross guard, Ned is being denied his help for people. Homer accepts only to be hurt even more. Finally Homer decided to let Ned's new wife Edna Krabappel handle it in order to get even with Homer to help Lisa from being miserable.
The next day Edna enters the room with Bart. After two minutes of Cantwell taking a bathroom break she finds that Bart has destroyed her class. So she quits instantly and tells Lisa that she doesn't like blondes and thinks that Lisa is a party-girl.