The author and the illustrator, who collaborated on the popular alphabet book < I>B is for Buckeye< /I>, have teamed up again for < I>Cardinal Numbers< /I>, the companion counting book for the great state of Ohio. This colorful and richly informative pictorial teaches children about numbers and math concepts by using people, places, and things specific to Ohio as examples. As the elementary age students begin to grasp these concepts, they learn more and more about their state in the process. < P< I>Cardinal Numbers< /I> is a wonderful tool for educators, and along with < I>B is for Buckeye< /I>, has become supplemental reading for every elementary-school classroom in Ohio.