Jake Boyman

Jake Boyman (aka Toilet) is the alias that Lisa used to join the boys' side of Springfield Elementary School, during the time when the school was split up into boys' and girls' halves.

History
As Jake, Lisa quickly picked up the nickname "Toilet", due to having toilet paper stuck to his shoe just after leaving the washroom. Although Jake initially had trouble fitting in with the other boys (and got beat up by Nelson), Bart helped him to become more accepted, after learning Jake's true identity.

At Bart's urging, Jake beat up Ralph Wiggum, albeit reluctantly as Jake apologized to Ralph for the beating while it was happening. Although Lisa felt bad about it, the Ralph-beating earned the respect of the bullies, who were impressed that Jake had picked on Ralph, "the most harmless kid in school".

Jake eventually won an award for his achievements in math. During the awards ceremony, when Jake went up on stage to accept the award, Lisa removed her disguise and revealed her true identity, saying that she had been Jake all along and shocking everyone by saying that the best math student in school was a girl.