I don't think I ever read like a 9th grader. Certainly not when I was in 9th grade! But if you/she wants an interesting exercise, how about reading the original H. Beam Piper Little Fuzzy and also Scalzi's re-imagining of it? I think there's some swearing in Scalzi's, and it's been too long since I've read the original to remember if it's there or not.

McCaffery's The Ship Who Sang? I liked the second (I think?) book in that series better than the first, though.

Verne for the classics. Adams for the fun.