Alex Rider series by Anthony Horowitz

I like these books for fun undemanding reading. They are aimed at boys, but any girl that likes James Bond movies will like these. The gadgets are fun (an iPod geiger counter and explosive bubble gum) and the adventure is constant. His jokes are terrible, but it adds to the fun. (He captures a bad guy with a giant magnet on a crane and says something about him being attractive.) My own kids liked them a lot at your age.