Tottoko Hamtarou

5th-grader Hiroko Haruna owns a hamster, and his name is Hamtarou. After moving into a new town, Hamtarou finds that he's in the company of lots of different hamsters, making up a group of hamster friends that go on crazy adventures through the city. Before they save Hiroko and other humans from nasty predicaments, however, they have to learn how to save themselves.
(Source: Anime News Network)