Planet Web Quest:

...a web quest for third grade.

URL: http://olc.spsd.sk.ca/DE/webquests/planetwq/WebQuest2.html#process

Nine Planets:
...A multimedia tour of the Solar System. (GIS has the Nine Planets CD to coordinate with this site.)
URL: http://seds.lpl.arizona.edu/billa/tnp/

The Nine Planets for kids
...Great site for kids to explore the planets and the sun.
URL: http://www.planets4kids.com

On-Line from Jupiter:
...the Galileo probe of Jupiter and its moons.
URL: http://quest.arc.nasa.gov/jupiter.html

Solar System Live:
...Click on Solar System for graphical displays of current orbital locations.
URL: http://www.fourmilab.ch/solar/solar.html

Views of the Solar System:
...is an educational tour of the solar system with images and information about the Sun, planets, asteroids, comets, and meteoroids.
URL: http://www.solarviews.com/eng/homepage.htm

Interactive Observatory:
...students can manipulate an interactive solar system simulator. They can create animations of
eclipses, generate a night sky for anywhere in the world, retrieve an image of where the planets are
located in the sky, and find fascinating information on astronomical phenomena.
URL: http://www.ScienceU.com/observatory/

Solar System Interactive Tutorial:
.... interactive solar system tutorial can be used as is for elementary astronomy lessons, or as an interactive reading and comprehension exercise. Students must read
the informative paragraphs and then click on the correct answer to the corresponding question before continuing on to the next featured planet.
URL: http://www.EnchantedLearning.com/subjects/astronomy/tutor/solarsystem/1

Solar System Online Activities:
....From NASA and its StarChild project, these interactive activities can be used by elementary students to learn about planetary orbits and objects found in the solar system.
URL: http://starchild.gsfc.nasa.gov/docs/StarChild/solar_system_level1/activity.html

The Solar System Activities Unit:
...several hands-on activities for third grade classes to integrate into your space/solar system unit.
URL: http://www.sasked.gov.sk.ca/docs/elemsci/gr3udesc.html#nex_solar

Amazing Space Web-Based Activities:
...Hubble Space Telescope offers a fascinating opportunity for educators and classrooms in this online, interactive educational project. Each activity unit includes teacher lesson plans and downloadable worksheets, should you not want to work entirely online. Activities include training to be a scientist (see Hubble Deep Field Academy); an Astronaut Challenge; Solar System Trading Cards; Black Holes; Whipping up your own Comets, and more.
URL: http://amazing-space.stsci.edu/

The Sun -- A Multimedia Tour:
...Who says you can't arrange a visit to our nearest star in this lifetime? This virtual tour is a must-see; loads of sun facts and pics and mini-movies will have your students entranced.
URL: http://www.michielb.nl/sun/kaft.htm