Enid Blyton 
Naughtiest Girl Again 

Elizabeth Allen, older and not having a spoiled personality, goes on to her second year for Whyteleafe School. She makes two enemies, Robert and Kathleen. Robert is a bully and Kathleen plays mean tricks on Jenny and Elizabeth. Elizabeth does not want to misbehave again, but someone tries to make sure that she does not forget her nickname of 'the Naughtiest Girl in the school’. Elizabeth tries to hunt down the sneak who is playing tricks on her and her friend Joan, resulting in many adventures.