Beatrice Kelly (portrayed by Ellen Foley) is the strict but reasonable principal of Zora Neale Hurston Middle School. She's the one who looks after the students and who the students can count on.

In the first season story arc "To Catch A Creep", due to some cutbacks in the school budget she was going to cut off the school's sports teams. Then she approved the idea of how the school's new school president would have a say in how they would not be cut off. She was unaware of who was smearing and mocking Alex. However she announced that when she caught the people involved doing it, she would punish them severely. Eventually, The Ghostwriter Team found out it was Calvin. She was furious and at first thought that both he and Jeffrey (the candidate Calvin was helping) were in on it together and decided to suspend the both of them. However Jeffrey pleaded and convinced her that he had no idea what Calvin was doing and had nothing to do with it. She believed him and cleared him and did not kick him out of the election. Then she suspended Calvin from school for a week. Also, when Janet Williams won the school election, she approved of her ideas to save the sports teams.

In the last first season story arc "Building Bridges", Mrs. Kelly attempted to cancel the school's annual "Star Jam" due to growing concerns of outside violence. But she turned her own proposal down when she received a petition to uncancel the "Star Jam" and rename it the "Community Jam." Then on the stage, along with Lenni she sang along to Lenni's song "Toe to toe and side by side" showing she too has some singing talent.

In the second season story arc "Who is Max Mouse?", the hacker Max Mouse tricked the students into thinking that Mrs. Kelly is dead, but of course she was not, proving it in an assembly with a brief moment of humor. At a later impromptu assembly she was furious, after firefighters came to the school instead of an actual ongoing fire, telling students that once Max Mouse was caught, he would report to her and to the police.