Final Grade is a novella written by R. L. Stine. It was first published in 1995 and was the thirtieth book in the Fear Street book series.
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Everyone thinks she killed her teacher.
Intense, competitive, Lily Bancroft had good reasons to hate him. She lives to win, and he was about to destroy her dreams. But murder? That was going too far, even for someone as driven as Lily.
She's innocent. But that hasn't stopped the whispers behind her back. Or the weird phone calls late at night. Then someone else is brutally murdered and suddenly Lily is drawn into a nightmare she can't begin to control. Will her final grade be her last?