I don’t tend to read that many young adult books, but this one looks like fun!
The description on Google Books:
Benevolence is not your typical princess. With her parents lost to assassins, Princess Ben ends up under the thumb of the conniving Queen Sophia. Starved and miserable, locked in the castle’s highest tower, Ben stumbles upon a mysterious enchanted room. So begins her secret education in the magical arts: mastering an obstinate flying broomstick, furtively emptying the castle pantries, setting her hair on fire . . . But Ben’s private adventures are soon overwhelmed by a mortal threat to her kingdom. Can Ben save the country and herself from foul tyranny?