(was it Le'Quin?) the Earthsea series
Ursula K. LeGuin.
Real nice lady, actually chatted with her for a couple of minutes at a presentation at Portland State University while I was as student there.
Yes, the Earthsea series is a good example, the first three volumes of it. The later work is aimed more at her adult readers who had read it as children, so many years had passed.
Ask a real librarian for good age related novels of the type.
Diffidently raises hand.
Caveat: I wasn't a Children's Librarian, so my knowledge is based upon what I read as a child, and what I shelved as the page in the Children's Library at the Multnomah County Public Library's Central Library in 1979-80, and what I've read since then. Professionally, I dealt with Adult Reference.
Lloyd Alexander's Prydain Cycle. Fantasy based on Welsh mythology.
H. M. Hoover. Pretty much anything she wrote, although I'd look at Children of Morrow and Treasures of Morrow first. Definitely falls in the SF end of the spectrum.
Diana Wynne Jones. More toward the fantasy end.
John Christopher's Tripods Quadrilogy and The Sword of the Spirits Trilogy. The Guardians is also very good. Science Fiction, although it takes a while to catch on to that with The Sword of the Spirits, where the science is being cloaked as magic.
Peter Dickinson's The Changes Trilogy, and The Blue Hawk. I'm not sure what I'd classify The Changes as, since at the very end you discover that the cause of what's happened is magical in nature, what it really deals with is the What If? of everyone in the UK suddenly being violently allergic to post-industrial technology. Violently is the operative term; if they come across working modern technology, they set out to pound it into little bitty pieces. It follows different children as they deal with the ensuing chaos. The Blue Hawk deals with an Ancient Egypt type setting, with the Gods being real; at the end you get the feeling that there was a previous high-tech society that had star travel, and discovered and harnessed some really ET non-material lifeforms to act as their Gods, which led to the establishment of the culture of the story, the culmination of which is their being released from the bindings placed upon them and their going back where they had been. The story proper focuses on the Acolyte they choose for the purpose of making that happen as a result of his actions. This description does not do it justice, at all!
Ellen Kindt McKenzie. Taash and the Jesters, Kashka, and The Golden Band of Eddris all share a setting, with the first two having major character overlaps; the three were published in reverse chronological order in regard to the story universe. The second actually sets the stage for the first novel, but they really should be read in the publication order, to avoid major spoilers. Drujienna's Harp. Fantasy.
Hmm. This list does seem to be rather fantasy biased.
Anne McCaffrey's Harper Hall Trilogy within her Pern series. Um, yeah, fantasy cloaked as science fiction...
Hokay... Yeah, do talk to your local Children's Librarian. They will be much more in touch with what's been written in the last 15-20 years.