
On his eleventh birthday Will Stanton discovers that he is the last of the Old Ones, destined to seek the six magical Signs that will enable the Old Ones to triumph over the evil forces of the Dark.
The intent was to then go back to the beginning of human history and read biographies of notable persons in chronological order --- unfortunately, my wife's work schedule changed, so that bedtime reading quit happening --- probably my kids were about to age out of this anyway, but it was an interesting endeavour, and one which I have been meaning to take up again for my own sake. EDIT: and, if I should ever have grandchildren, inflict on them.
I read the first few HP, and thought they were dreadful, and thus never read the later ones, so maybe I'm not the person you want advice from, but here are some recommendations of novels/novelists in the same genre (fantasy novels, written for children, that hold up for adults):
Nearly anything by Dianna Wynne Jones, but I particularly enjoyed The Lives of Christopher Chant, Archer's Goon, and of course Howl's Moving Castle.
Susan Cooper's famous Dark is Rising series. Half the series is more normal-kid (starting with Greenwitch), half is more special-magic-kid (starting with The Dark is Rising).
Garth Nix's Old Kingdom, starting with Sabriel.
While China Mieville is very much not a children's author (really! don't buy a random mieville book for your young niece/nephew, really don't!), Un-Lun-Dun is an amazing book in this genre.
