J.B.
I need to know where you are in the Atlanta area, but if you're intown, you are welcome to join the Grant Park Parent's Network -even if you don't live in Grant Park. We have playgroups for every age child and there are several activities during the year for the entire group. Go to www.grantparkparents.org for more info. I know there are lots of parent groups and playgroups around town in other neighborhoods too.
Other places that are fun for 18 month olds -The IMAGINE IT Children's Museum downtown near World of Coke and The Aquarium; The Aquarium, the zoo, The Little Jumping Bean or Monkey Joe's (inflatable play places), Peachtree Dekalb Airport's playground -right by the runways off Clairmont Road -the children can watch the private planes take off and land.