Part of the Cam Jansen chapter book series featuring a fifth-grade girl with a "photographic" memory. These books are not whodunit type of mysteries, but each story contains a conundrum, which Cam's eidetic memory helps to solve. The protagonist and her bff are a bit old for a chapter book. The books in the series are all short, (less than 60 pgs each) quick reads. They can be read independently of one another, and are easily understood if read out of order. Published in the 1980s, the books are somewhat dated, mostly in terms of technology (i.e. cameras requiring film that needs developing, pay telephones in boxes, kids running around without a cell phone or any way to contact parents/authorities, etc.). 
 In this book, Cam and her best friend, Eric, discover a dog-switching scheme and go after the perpetrator.