Suzanne Collins other series Gregor of the Underland is technically aimed at younger kids but like Harry Potter they get darker and darker though the series. I know they aren't tchnically Sci Fi, everyone needs some fantasy in their lives!

And i agree with the Wizard of Earthsea books suggestion from above, as a teacher i would also do a comparison between the second two and the Studio Ghibli version from a couple of years ago (kids like watching movies :D )

I never read like a year 9 kid either ;)