Young Cam Jansen and the Zoo Note Mystery

　　Cam and Eric's class is going on a field trip to the zoo. But Eric can't find his permission slip, and without it, he can't go on the field trip. Where did it go? Did he drop it somewhere? Was it stolen? Will Cam Jansen's amazing memory help to find Eric's permission slip in time? Or will he have to sit in the principal's office all day while the other children go to the zoo? Hurry, Cam, time's running out!

　　Cam的班級要去動物園校外教學，但是Eric卻找不到他的家長同意書，怎麼辦，這樣不能去玩耶…