What to do with kids in Atlanta?

I like the convenience of the city center for entertainment. In a few walkable blocks there is the World of Coca-Cola, Georgia Aquarium, Centennial Olympic Park Dr NW  (fountains, green space, and playground), Imagine It! The Children's Museum of Atlanta, and the new ferris wheel (EYE).

The Zoo Atlanta is great in and the The Coca-Cola Company can be fun for kids it's also in a nice part of town to walk shop and eat! 

You could spend an entire day at Stone Mountain Park. Awesome for kids. There is a great ropes course, miniature golf, train ride, biking, hiking and much more. 

Great answers so far! There's also LEGOLAND Discovery Center Atlanta at Lenox, Stone Mountain and the Imagine It! The Children's Museum of Atlanta. Lots of great stuff for families! Check out Field Trips with Sue and Atlanta with Kid for more. 

Definitely the Georgia Aquarium. Also the Center For Puppetry Arts. There's also a great science museum north of Atlanta, but I can't remember where it is exactly.

The Georgia Aquarium is fabulous!  Beluga whales and a wonderful dolphin show.  It's within walking distance to the World of Coca-Cola-the world wide tasting room is worth the visit alone-the kids will love tasting all the different varieties and seeing where they come from (make a geography lesson out of it!).  Lastly, take them to Mary Mac's Tea Room for a taste of true southern comfort food.  They'll enjoy the decor, hospitatility and looking at tall the famous photos on the walls.