Martin Prince, or Martin Prince Jr., is a character portrayed as the teacher's pet. He's the stereotypical geek who likes to work and has quite a playful personality. Much like geeks, he has passion for science, drab fashion sense and science fiction. He is one of the easiest targets in the Springfield Elementary School playground. He is thus constantly bullied by the likes of Nelson Muntz, Jimbo Jones, and others.
Despite his animosity with a few characters, he remains gentle and kind-hearted to everyone. The most notable examples are Bart Simpson and Nelson Muntz. Bart and Martin have often joined forces and taken a few adventures together, and despite often getting beat up by Nelson, Martin continues to try to be his friend. Sometimes, it is even hinted that Nelson wouldn't mind being Martin's friend, but obviously doesn't to keep his bully bad-guy image.
Prince is also a reputed fan of poetry, and often quotes and creates verses - sometimes while gracefully dancing around, which amplifies his happy class-nerd personality.