Hermione had always known she was smart.
She quickly proved it in classes; by the end of her first week, she was at the top of all of them. The severe Professor McGonagall had even smiled at her, something that was apparently a rare occurrence. She didn't quite have a favourite subject yet, as she found all of them quite fascinating. Unsurprisingly, she soon found her sanctuary in the school library, which was piled high with so many books that would take a lifetime to get through.
She never told anyone how prepared she'd been to read them all.