Whales on Stilts! by M. T. Anderson
Lily Gefelty's father works for a mad scientist who wears a sack over his head. When she overhears him say that he wants to take over the world, her oblivious father assures her, "Honey, sometimes adults use irony. They don't really mean what they say." Nonetheless, the 12-year-old calls on her two best friends, Katie Mulligan, the star of the "Horror Hollow" novels (think "Goosebumps"), and Jasper Dash, also known as the Boy Technonaut (think "Tom Swift"), to investigate. The trio soon learns that Larry does indeed plan to conquer the world using mind-controlled whales on stilts with laser-beam eyes. No adult will believe them, so it's up to the kids to save the Earth.

This was a very fun entertaining read. Book 2 is already in the works. I love how it shows sometimes the kids do know best.