Janice Avery is the main antagonist in Bridge to Terabithia. She is a heavyset eighth grader who bullies younger children at school.
Janice and her two friends, Wilma and Bobby Sue, go to the same school as Jess Aarons and Leslie Burke. They commonly bully younger children, for example, Jess, who is teased for being poor, and Janice even throws a little girl's sandwich on him on the school bus. During break time, they usually stand in front of the girls' bathroom and put a fee on entering.
Leslie, frustrated from being bullied, sits on the back seat of the bus where only older students sit. Jess, who sees Janice, Wilma, and Bobby Sue coming, rushes to help her. Janice tells them to get out, causing Jess to thoughtlessly insult her for her obesity. As revenge, she later pretends to be tripped by him, leading the bus driver to order him to walk home.
When Janice steals Twinkies from Jess' younger sister, May Belle, Leslie decides to stop her. At first, she gets a group of younger children, and they head to the bathroom shouting, "Free to pee!" However, the girls only laugh at them. Jess and Leslie then decide to play a prank on Janice. They write a love letter "from Willard Hughes", the object of her affection, who "wants to see her after school", and Jess hides it in her notebook. The next day, she really waits for Willard after school, but he does not appear. She speaks to him in front of all his friends, much to his surprise. When she finally realizes the letter was fake, all the students who see it laugh at her.
Jess and Leslie feel good due to their victory, until they hear Janice sobbing in the bathroom. Leslie comes in to talk with her, and discovers that she is abused by her sadistic father. Leslie advises her to pretend she has no idea what Wilma and Bobby Sue are talking about, and the students soon forget about it. Since then, Leslie develops sympathy and a friendship with Janice. The police are recently called to her house, and now the whole seventh and eighth grade know she is beaten there, so they ostracize her.
After this, Janice stops being a bully and becomes an outsider and a friend of Leslie.
- One of the creatures Jess and Leslie fight with in Terabithia is a troll resembling Janice.
- The connection between Janice and the troll is given a subtle foreshadowing when Leslie first talks to her. She compares her bathroom tolls to the story of troll bridges.