Book excerpt: Fans of Dav Pilkey's The Adventures of Ook and Glook and Patricia Reilly Giff's ZigZag Kids will flock to this chapter-book mystery series full of slapstick humor and silly situations by the wildly popular Tony Abbott, author of the Secrets of Droon series. Jeff, Mara, Brian, and Kelly are Goofballs and proud of it. Goofball private eyes. Together, they solve mysteries. How do they discover the truth? They use funny disguises, nutty inventions, and their secret weapon: Sparky the Goofdog! Objects have been disappearing from Ms. Becker's kindergarten classroom - blocks, an easel, even the class goldfish! Luckily, the Goofballs are ready to go undercover to help their former teacher learn the truth. But posing as teachers is hard work, especially when the entire class may be as smart as Kelly, as observant as Jeff, as creative as Mara, and as goofy as Brian. Everyone's a suspect, and every time the Goofballs turn their backs, something else vanishes. Soon, the whole classroom will be gone! Have the Goofballs been out-goofed? These young sleuths have never failed so solve a case, and they don't intend to start now!