I may not be the target audience (I haven't been a "Young Adult" for about 20 years), but I loved The Kontakion Gene. It's a somewhat unlikely mix of action, choir practice and everyday school life. I don't want to spoil too much, but there's great action-packed fantasy/science fiction elements that sit perfectly in the Wells setting, and the author absolutely captures what it was like being a teenager - trapped between being an adult and a child. Although my childhood wasn't quite as exciting as the protagonist, Tom's.
I'll be getting my nephew to read it as soon as possible, and look forward to the next book in the series coming out. More please!