Book where the main character has to hide magic powers/what have you from those around them

Looking for a book where the main character has some kind of special magic powers or whatever that they have to hide from those around them. Preferably in a school setting or similar; basically where the main character interacts with a lot of people that know them.

Ideally not "superhero" powers; I'd prefer, for example, the main character having magic over being able to fly.

Also, I'd like there to be other people with powers also.

Preferably, no one would know in the beginning, but then the best friend finds out, then other people/parents, etc, until everyone knows.

The longer the better, the darker the better. Thanks!