Kids.Gov

https://kids.usa.gov/learn-about-the-states/index.shtml

50 States

http://www.50states.com/

United States Census Bureau

https://www.census.gov/schools/facts/

Learning for Kids

http://netsmartkids.org/united-states.htm

US Geography

http://www.ducksters.com/geography/usgeography.php

US Mint for Kids

https://www.usmint.gov/kids/