Dear 1143211:
The best way to introduce Celestia to educational settings in a school is to first decide how you want to use it. Basically, (1) you can use it on your teaching computer by connecting it to an LCD Projector, and putting it through its paces in front of your class. By using some of the cel:url links in the educational activity series, or by inventing your own, you can showcase hundreds of places in Celestia to your student audience, from planets to black holes.
The 2nd approach is to load the program and the Celestia Educational Activity series on a class set/lab set of school computers, sit each student down in front of their own computer, turn out the lights, put on some soft "space music", and let them explore the universe personally ... by flying the Celestia spaceship. That is the approach I take, and is the one that has made my Astronomy course the most popular in the entire high school of 3,100 kids.
To get a better feel for how it all works, read the several postings in this forum thread:
http://shatters.net/forum/viewtopic.php?t=10058&start=0
Once you decide how to use the program, it is not difficult to implement it. It is free for download and has only a modest fee when purchased on CD. Your school will have no problem installing it. The biggest problem will be whether your computers can run it. Unless they have a reasonably fast video card, Celestia will run slowly on many school systems.
Feel free to email me separately to discuss specific questions you may have.
Regards
Frank