story line pitch

a girl called lily who is 14, is bullied and locked in a cupboard but finds a pencil case which gives her money, the pencil case has alot of writing (codes) which lily has no idea what they're meant for. she finds money in the pencil case every morning but when she tries to become popular with other kids in school by telling them about the pencil case no one believes her and the pencil case stops producing money so at the end she decides to find out who and why and how this pencil case works, tries hard to find the owner.....