Settle the argument of who's is truly bigger with this planet size comparison tool. View a image of each planet as it's real ratio.
http://ictmagic.wikispaces.com/Science
This is a great child-friendly place to find out about the planets and the universe. Click on the topics to see lots of info, images and games.
http://ictmagic.wikispaces.com/Science
Nice way to calculate how to build a model solar system.
You put the measurements in for the size of the sun (in inches OR millimetres) and the rest (including sizes of planets and distances from the sun) is calculated for you.
Stargazing Live is a wonderful BBC programme on air in January. The site has lots of great resources to help you understand the night's sky.
http://ictmagic.wikispaces.com/Science
A realistic walk-though of a 3-D model of a Mars base for the first humans to land on Mars. Over 100 images representing a Mars habitat, a greenhouse, a Mars car and robot rovers.