http://www.microsoft.com/kids/freestuff/

Volcano Adventure Activity Center
Download Leapin' Lava Game

Whales & Dolphins Activity Center
Download Bring Back the Beluga Game

Lands on Mars Activity Center
Download Mars Rover Race!

Explores Bugs
Download Ant Maze Game

Explores the Rainforest
Download Night Stratification Game!
Download Escaping Monkey Game!

Explores in the Age of Dinosaurs
Download Skeleton Puzzle Game!
Download Meteor Meltdown Game

Explores Inside the Earth
Download Panning for Gold Game!
Download Volcano Builder Game!

Explores the Ocean
Download Crab Chase Game!
Download Sand Castle Builder Game!

Explores the Solar System
Download Venus Game!