PUDDLEJUMPERS, by Mark Jean & Christopher C. Carlson, Hyperion Books, paperback $7.99; age 9-12.
Thirteen-year-old Ernie Banks lives in the Lakeside Home for boys and is always getting into trouble. As a last resort, Ernie is sent to a farm to work for three weeks. What he finds is a mystery-the owner's son was kidnapped 10 years ago and the only clue was a red quilt. Ernie teams up with Joey, a neighbor, to solve the mystery and together they discover an underground world of 11-inch creatures called Puddlejumpers. Only after helping these creatures can Ernie really go home.
THE UNKNOWNS, A MYSTERY, by Benedict Carey, Amulet Books, $16.99; age 9-12.
In a trailer park, next to the energy plant, people are going missing. No one seems to care until Di and Tom's favorite neighbor, Mrs. Clarke, is one of the missing. The pair find a clue in her trailer-a math problem. This clue leads them through a journey of deep tunnels into the garbage dump and underground work stations. Di and Tom learn the truth about the energy plant, the people who run it and, best of all, the meaning of true friendship.
THE LAST OLYMPIAN, by Rick Riordan, Hyperion Books, $17.99; age 9-12.
In this the fifth and last book of the series, Percy Jackson is fighting for his life. Kronos and his army are stronger than ever and headed for New York City. Percy and his friends, the half-blood demigods, are left to battle Kronos and save New York and Mount Olympus.
THE MAGIC THIEF: LOST, by Sarah Prineas, HarperCollins, $16.99; age 9-12.
Conn, an orphan who lived in the streets, was once a pickpocket who picked the pocket of the wrong person-or the right person depending on how you look at it. Conn is now apprentice to the wizard Nevery, who must find out where all the magic is going. Together Conn and Nevery battle the dark shadows, talk with fire, rescue the queen's daughter and save the magic.
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