Steel Trapp: The Challenge by Ridley Pearson (Disney Editions) is a middle-grade thriller about a kid named Steel Trapp, who gets involved in solving a kidnapping and terrorist plot on the way to the national science fair. His foil is Kaileigh, a runaway who's on her way to the science fair too, and whose help Steel will need if he's going to figure out why this strange woman was trying to leave a briefcase on the train, and what it has to do with a missing person.
I liked this more than I thought I would, especially given how much I hated an adult thriller I read by the same author. This kid thriller doesn't have as much science or tension or spies as I'd like, but unlike adult thrillers, it doesn't have the casual misogynism, racism, etc. that so many do. It's tough to get middle grade kids in on the action, but this worked for me.