If you are interested in science that is beyond Earth, check out Amazing Space! You can learn all about space with doing many cool activities.
BioDigital is a science program that features a 3D human body. The free program allows you to explore organs, systems and body parts.
Edumedia – Sciences offers science simulations that cover all types of science topics great for discussions and introducing topics.
EverBlock is an actual business site but it has a great free virtual Lego type building area. There are many building options to work with.
Fantastic Contraption is a physics game that teaches problem solving skills and is a great way to create team building activities without all of the materials.
How Stuff Work does just that! Teach how stuff works!
National Geographic Kids is a highly engaging site that offers a variety of topics, games and activities for kids!