Wow! 4 days of posts about one of my favorite topics and I missed it... until now. But I won't add much except to say that yes, you can protect any media displayed on the web from all copy except by taking a photograph of your computer screen with a camera or video recorder. The reproduction may not be the best but some will distribute videos of such degraded quality.
My colleagues field a lot of support enquiries from all types of people and entities wanting to copy protect media and they find that some can quite silly about it because they also want that same content to be indexed by search engines.
For those interested in the most effective solutions, check out the ArtistScope site. They provide a variety of solutions for different media including what has to be the most secure web browser on the planet and one that is becoming more and more popular with online schools.