Description from Goodreads:
Smart girls aren't supposed to do stupid things.
Madelyn Hawkins is super smart. At sixteen, she's so gifted that she can attend college through a special program at her high school. On her first day, she meets Bennett. He's cute, funny, and kind. He understands Madelyn and what she's endured - and missed out on - in order to excel academically and please her parents. Now, for the first time in her life, she's falling in love.
There's only one problem. Bennett is Madelyn's college professor, and he thinks she's eighteen - because she hasn't told him the truth.
The story of their forbidden romance is told in letters that Madelyn writes to Bennett - both a heart-searing ode to their ill-fated love and an apology.
I rarely get this excited about contemporary romance books, but this just sounds so great that I can't pass this one. Come September already!