Sooner Boomer writes "This is a follow up on a question I asked of Slashdotters a few years ago. Not having found "Mrs. Boomer", I'm left with spoiling the daughters of my younger brother and sister. The oldest two are about 17 and starting college. The youngest two are 14/15. I've given them a wide range of science fiction and fantasy, everything from Heinlein and Asimov to the modern-day vampire stuff and Terry Pratchett. What should be on a "must read" list, and how does this change with age? Are there any books of this genre specifically aimed at older teens? Any specifically aimed at girls/young women?"