Splat is so scared of his first day of Cat School that his tail moves with worry. He needs a friend so he takes his pet, a mouse named Seymour, with him to school. Mrs. Wimpydimple covers lots of topics such as self-esteem and nature. When Seymour gets out of Splat's lunchbox, the cats chase after him. The teacher saves Seymour. By day two, Splat's tail moves with excitement.