If your child likes fantasy but is too young for Harry Potter, here are some more age appropriate titles.
(The age ranges listed are a guideline, it all depends on the individual child and his/her reading capacity).
Faerie Realm:
Faerie Realm by Emily Rodda (age 7-10)
Disney Fairies by Kiki Thorpe (age 6-10)
Fairy Chronicles by J. H. Sweet (age 7-12)
Fairy School Drop-Out by Meredith Badger (age 9-12)
Fairy Tale:
Fantastic Creatures:
BFG  by Roald Dahl (age 9-120
The Dragon's Child by Jenny Nimmo (age 7-10)
Dragons Keepers Series by Kate Klimo (age 8-12)
Dragons of Deltora by Emily Rodda (age 9-12)
Dragons of Wayward Crescent by Chris D'Lacey (age 7-10)
Dragonslayer Academy by Kate McMullan (age 9-12)
How to Train Your Dragon by Cressida Cowell (age 8-12)
Pixie Tricks by Tracey West (age 7-10)
Spiderwick Chronicles by Tony DiTerlizzi (age 6-10)
Gateway/Magical Object:
Magic Tree House by Mary Pope Osborne (age 7-12)
Secrets of Droon by Tony Abbott (age 7-10)
Time Warp Trio by Jon Scieszka (age 7-10)
Heroic Adventures of Hiccup the Viking by Cressida Cowell (age 8-12)
Never Land by Dave Barry (age 4-7)
Other Worlds:
Secrets of Droon by Tony Abbott (age 7-10)
Dragons of Deltora by Emily Rodda (age 9-12)
Lily Quench and the Dragon of Ashby by Natalie Jane Prior (age 4-7)
Araminta Spookie by Angie Sage (age 7-10)
Ghosthunters by Cornelia Funke (age 7-10)
Ghostville Elementary by Marcia Thornton Jones (age 7-10)
Ink Drinker by Eric Sanvoisin (age 9-12)
Witchcraft & Wizardry:
Avalon by Rachel Roberts (age 8-12)
Magic Shop by Bruce Coville (age 8-12)
Robe of Skulls by Vivian French (age 8-12)
Sister Magic by Anne Mazer (age 7-10)
Witches by Roald Dahl (age 9-12)