We have digitized a small sample of constellation images for workshop participants to use in order to build an astronomy lesson. Links to copyrighted material are broken on the online version of this document.
You may also use sounds and images in the samples directory. If you are ambitious (and if the internet hookup is working) you can link your lesson directly to NASA or the Hubble!
For some interesting astronomy software for education go to Gettysburg College and look at The Contemporary Laboratory Experiences in Astronomy (CLEA) project.