Here is the idea, id love to do this tonight if possible.
The main character (you) is a girl who loves basketball but the best basketball team in the state happens to be an all boys team at an all boys school. You disguize yourself as a boy to try out, you succeed, but now you gotta live in the dorm with the boys of the school and room with the team captain.
I had a preference if you dont mind, she is kinda busty so she needs to wrap herself under her shirt. What do you think? all that is just the starter.
There is another version with just a small tweek.
Instead of her wanted to go for basketball, she wants to go cause her childhood friend (male) is moving far away to go there and she wants to go with him, this starts off as a purely innocent gesture. She rooms with him posing as a girl.