Math and numeral games for kindergarten through sixth grades. 

http://www.rainforestmaths.com/

Fun interactive games for young children that reinforce numbers, letters and using the mouse.

http://www.poissonrouge.com

Educational games created by the Australian Broadcasting Corporation to help younger children understand numbers.

http://www.abc.net.au/countusin/games

Explore a timeline of Renaissance art and innovation, commission an artwork as a patron of the arts, design your own innovation, and much more, all enhanced with quirky visuals, irreverent humor, and engaging interactivity that reveal the ways that Renaissance life and culture resemble our own.

http://www.renaissanceconnection.org/main.cfm 

http://www.pestworldforkids.org/learninggames.html

How can zoos help save endangered species? By breeding them in captivity, in hopes of someday releasing animals back into their original habitats. This interactive places you in charge of a breeding program for endangered tigers. Choose from several breeding plans, then make the best matches to ensure tiger survival. Along the way, you'll learn about tiger genetics and the basic rules of inheritance.

http://www.minnesotazoo.org/education/games/matchmaker/index.html  

A unique role playing curriculum that empowers kids to join the environmental discussion about the world's wildlife conservation issues.

http://www.zamsquest.com/index.php

http://hubblesite.org/explore_astronomy/black_holes/modules.html

My Pop Studio is a creative play experience that strengthens critical thinking skills about television, music, magazines and online media directed at girls.

http://www.mypopstudio.com/index2.php 

Architect Studio 3D brings to young architects everywhere the exciting process of designing a home — hands-on. Starting as real architects do, with a client who has lifestyle preferences and a site that has its own environmental considerations, you will use your imagination to design your own architectural solutions.

http://architectstudio3d.org/AS3d/design_studio3d.html