Finding The night lark

Layla lark has been invited to a prestigious school for the gifted, based on her gift with numbers and math. However when she arrives at the "school" she finds out she was invited under false pretenses, as well as some interesting circumstances, not to mention, it's not really a school at all, she now has the choice to stay and be sworn to secrecy or have all her memories wiped of everything she has found out, and go home, in the knowledge her choice will decide her future.