When I think of "derivative", I think of Eragon, a story that seems to be the result of a three-way between Star Wars, Lord of the Rings, and The Dragonriders of Pern. When I think of "derivative", I think of City of Bones, which is like an alterna-version of Harry Potter. As I read City of Bones, I found so many similarities between it and Harry Potter that I actually started keeping a list. Here is that list:
Main Character Name
HP: Harry (male)
CoB: Clary (female)
Book Summary
HP: Harry comes of age as he discovers that he is part of a magical hidden world, and that he himself has powers.
CoB: Clary comes of age as she discovers that she is part of a magical hidden world, and that she herself has powers.
Main Character Has a Special Mark
HP: Harry's scar on his forehead
CoB: Clary's rune that Jace draws on her forearm
Main Character's Parents/Guardians
HP: Harry's Aunt Petunia and Uncle Vernon, who knew about the magical world but kept it a secret (as did family friend Mrs. Figg)
CoB: Clary's mom Jocelyn, who knew about the magical world but kept it a secret (as did family friend Luke)
Non-magical People Are Called
HP: Muggles
CoB: Mundanes
Early Introduction to the Magical World Involves
HP: Traveling to a magical educational location (Hogwarts), which is hidden from Muggles with spells.
CoB: Traveling to a magical educational location (The Institute), which is hidden from Mundanes with spells.
Authority Figure at Educational Location
HP: Elderly Dumbledore, Headmaster at Hogwarts, who has an intelligent pet Phoenix
CoB: Elderly Hodge, Tutor at The Institute, who has an intelligent pet Blackbird
Main Character Discovers Parent's Fame
HP: Harry discovers that his parents (Lily and James, both dead) are famous in the magical world
CoB: Clary discovers that her parents (Jocelyn and Valentine, presumed dead) are famous in the magical world
Evil Figure in Power 12-15 Years Ago
HP: Voldemort, presumed to be dead but now there are signs that may indicate otherwise
CoB: Valentine, presumed to be dead but now there are signs that may indicate otherwise
Goals of Evil Figure
HP: Voldemort: Wants Wizard bloodlines kept pure and for Wizards to rule over Muggles and other magic beings
CoB: Valentine: Believes that Downworlders are inferior and should be exterminated
Evil Figure Seeks This Object to Secure Power
HP: The Philosopher's Stone
CoB: The Cup
And I'm sure there are more similarities that I haven't thought of yet.