Here are great sources for media licensed for your use. Check out Ronnie Burt’s page on The Edublogger for more info!
Creative Commons Search – Search many sites at once *Our Favorite!
StockVault.net – Free images from photographers around the world
Kozzi.com – One free photo per day
FindIcons.com – Huge resource for avatars or small images
Flickr Advanced Search – Use advanced search filters to show only CC licensed images
Morguefile – Free stock photos (Thanks Sue Lyon-Jones for link in comments!)
Open Clipart Libary – Public domain clipart (Thanks Sue Lyon-Jones for link in comments!)
That being said, you (or your students) can’t necessarily use parts from videos on YouTube (or other sources) to make mashups or as part of another video. Be sure to have permission to use any video that you are cutting, making changes to, or adding to a project.
Curriculum and Text
Wikipedia – Quote away (with a link back) to any information you find on Wikipedia
Curriki – An open curriculum community
Collaborize Classroom Library – A growing resource for discussion questions, lesson plans, and more
You won’t be able to add student resources from most textbook companies or purchased curriculum – so be careful and make sure you have permission before doing so!
Related Posts and More Info on Copyright