Locate photos, music, etc. safe to use in the classroom.
ccMixter - Creative Commons-licensed music for use in school projects, videos, etc., all for free with proper attribution.
flickr Creative Commons - Creative Commons-licensed photos.
Free Music Archive - Music licensed by Creative Commons for free and reuse with proper attribution.
NEN Gallery - United Kingdom's National Education Network gallery contains thousands of FREE photos, videos and sounds, all available for use in the classroom. Great site!
Pics4Learning - A library of images safe, copyright-friendly, and free for use in the classroom. Copyright information is included with all images for proper attribution.
Pixabay - A repository of stunning public domain photos free to use in any digital or print format.
Purple Planet - Royalty-free music available for download for free for use in any web-based project, including YouTube, with proper attribution.