Copyright and Creative Commons can be confusing topics. There are many variables that apply to every situation so it is hard to layout hard and fast rules that apply to every scenario. To help educators understand and navigate the landscape of Copyright and Creative Commons, I've put together a short list of helpful resources.
Dr. Wesley Fryer's presentation Copyright for Educators is the absolute best presentation I've seen on the topic. The Slideshare presentation is available with audio from his presentation. It's an hour long, but it is easy to listen to and you'll pick up tons of useful information.
For my Canadian friends the rules of copyright are different than they are for me in the United States. David Wees has a good presentation about Copyright for Canadian educators.
The Copyright Foundation offers a thirteen page guide (link opens PDF) to Copyright for Educators. Included in the guide is a glossary of important terms. At the end of the guide you will also find some lesson plans that are available on the Copyright Foundation's curriculum pages.
For helping students learn about Copyright Taking the Mystery Out of Copyright is a use resource produced by the Library of Congress. Taking the Mystery Out of Copyright is intended to help elementary school students understand the purposes and functions of copyright.
YouTube's Copyright School is a four minute video with a few multiple choice questions at the end. As The New York Times reported last year it's where Google sends their Copyright violators before they can have their accounts reinstated.
Disclosure: Common Craft videos can be viewed for free online but to download them or embed them you do have to be a subscriber to their service. In the interest of full disclosure I will tell you that I have an in-kind relationship with Common Craft which means that I have received a subscription in exchange for advising Common Craft on some product offerings.