Lexington Park is the most developed area near the base, and there's a lot of community activities that you can find there. For kids, there's the Air Museum at the base:
Patuxent River Naval Air Museum
Also, you can try the forums at
Southern Maryland Online™ - Your on-line community for Calvert, Charles, and St. Mary's Counties.™
It's a pretty good resource for people to meet and connect in the the local area specifically. Hopefully this helps, if you find yourself looking for something to do or in need of more information on the area, PM me and I'll be more than happy to help point you in the right direction!
Good luck on the relocation!