Hangman
Play Hangman and test your knowledge about space. Try to guess the mystery word and fill in the correct letters in the blanks. Each incorrect guess brings you closer to being "hanged." Words that are used range from "Aries" and "Pluto" to "Astrochemistry." The game is found at KidsAstronomy.com.
Cross-Word
Solve a fun crossword with questions involving planets, stars and astronomical equipment. There are three different levels of crosswords; the easiest have questions such as "Closest star to Earth?" The second and third levels have harder questions such as "Distance light travels in a year?" You can submit the answers and have them checked. The crosswords are found at KidsAstronomy.com.
Matching Game
Solve the Matching Game at Quia.com and test how much you know about the planets. You match the planet with different facts. For example, the largest moon is Titania, name of the goddess of love and beauty. There are several different games, so you can match several different facts to all the planets in the Solar System. The same site has other matching games as well. Try "Stars and Galaxies Vocabulary" to see if you can match words such as "protostar," "nova" and "binary star" with the right descriptions.
Space Explorer
Solar System Explorer consists of several different games where you explore the planets in our Solar System. Click on planets, moons, comets or asteroids and explore each in turn. For instance, visit the planet Jupiter and play the Juno game, where you help NASA New Frontiers mission Juno to orbit Jupiter 32 times. You find the games at SpacePlace.Nasa.gov. This site has plenty of background information on space missions, along with photos and illustrations from space.
Make a Solar System
At KidsAstronomy.com you can create your own solar system. Add planets, comets and asteroids to the sun in the middle. You can add several versions of Pluto and drag the planets where you want them. The planets are circling around the sun, and this allows you to understand the different orbits that planets have. Planets can "catch up" with each other and collide. Planets that collide burst into flames.
Space-On-Air
Play Space-On-Air and remove as many sticks as possible while keeping the transmitter above a dotted line. There are 30 different levels in this game, and your understanding of how much fun physics can be increases while you figure out different ways to remove the sticks without ruining the construction. You find the game at PhysicsGames.net.