S08E07 Lisa's Date with Density
At school, Nelson is caught with a cache of stolen items in his locker (including the "H" hood emblem from Supt. Chalmers' car) and is assigned to do chores with Groundskeeper Willie. Lisa is caught observing the goings-on and is assigned detention, where she develops a crush on Nelson. Lisa tries to reform Nelson, and it works for awhile. However, as the old saying goes, you can't teach a juvenile delinquent new tricks and it isn't long before Nelson is back to his old ways; he and his buddies had been caught throwing spoiled food at Skinner's house and tries to lie to Lisa about his participation in the whole thing, but ultimately lets slip the truth. Meanwhile, Homer obtains an autodialer and decides it will help him make easy money through his "Happy Dude" telemarketing scheme. Homer is eventually caught and made to use the autodialer to call back everyone he scammed in apology. Which he does ... then he asks for more money as part of a "Sorry Dude" scam.