It's the "School" pennant Homer made in the "The Wizard of Evergreen Terrace" episode of the Simpsons.
In the show Homer becomes obsessed with Thomas Edison and has to go to the library at the elementary school because he can't go to the adult library anymore because of reasons.
This was the longest pencil I could find.
It looks a little different than the one in the episode, but maybe if there were more shots of it one of them might look like this.
The Simpsons and things in their environment would change shape a bit from shot-to-shot.
That's my excuse...