Sammy the Seal: 04/28/15
Sammy the Seal by Syd Hoff is about a seal who needs a break from zoo. So the zookeeper gives him the day off. Sammy heads into to town, meets all sorts of folks and ends up at a school, where he learns to read!
It's a silly premise, the what if being a zoo animal is a job like anything an adult human might do. There was a year long anime series that had the same premise: Polar Bear Café which had characters who either worked at the zoo or at other jobs around town.
There's just something endearing about animals and people living together — animals working side by side as salarymen.