Twenty guinea pigs can be too many--especially if all of them are crammed on a small and tipsy boat. In this charming and boisterous book about subtraction, the guinea pigs begin to jump ship, each in his or her own funny and unique way. While children follow the story of the ever-shrinking gang of guinea pigs, they can count the furry pals leaping on and around oversized numerals representing the number of cavorting cavies on the page. A simple equation that shows the subtraction is printed along the bottom of each spread, reinforcing the concept.Like its successful predecessor, One Guinea Pig Is Not Enough, this book tells a story while teaching a number concept. The irresistible artwork bursts with action, color, humor, and clever details that readers have come to expect from the beloved Kate Duke.