John

4th Grade Male Rabbit is an unnamed fourth grader who debuted in the episode Arthur's Eyes. Not much is known about this character other than that he is in fourth grade and was in the same kindergarten class as Prunella, which was shown in the episode Brain's Shocking Secret.

He has been seen in the background of many episodes usually walking around the hallways, at lunch, or at the playground at school, but is seen outside of school occasionally.

Sometimes he is substituted for Steve, but appears to not be related to either Steve or Steve's sister Maria in any way, but is most likely friends with both of them.

He has been seen hanging out with both third graders and fourth graders alike. His personality is a mystery though he appears to be nice to the other kids despite never speaking in any of the other episodes.

Appearance
4th Grade Male Rabbit is a rabbit with a white complexion. He wears a tan collared shirt with long sleeves, dark cream colored khakis, has on very noticeable red suspenders, and cream colored shoes.

He also wears glasses just like Steve does and has a blue backpack. In the episode, The Blackout, his winter attire consists of a chestnut brown coat and a blue scarf.

Trivia

 * This character may have a little sister. His sister's name is Lisa.
 * Sometimes this character replaces Unknown Male Rabbit in some episodes like Cents-Less where he was seen in one scene and then the scene changed completely with a new character.