His only appearance is when he is fired by Principal Skinner. Seamus blames his firing on Willie, and the two fistfight:
- Groundskeeper Seamus: Is this your doin', Willie? I'll turn your groin to puddin'!
- Groundskeeper Willie: Ach! Ya speak like a poet, but ya punch like one too!
Willie appears to have won the fight after knocking Seamus down.
Non-Canon AppearancesHe appears in The Permanent Record Room, where he gets mistaken for the Green Goober, a parody of the Green Goblin. Willie turns into Willie Webspinner and the two fight.
- Episode – "I Am Furious (Yellow)"
- Comic book – The Permanent Record Room
- Video game – The Simpsons: Tapped Out