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So, they all exist under a Creative Commons license, which the CreativeCommons.org website describes as "a set of copyright licenses and tools that create a balance inside the traditional 'all rights reserved' setting that copyright law creates."
We make them available to you here so that you can pull elements from them, learn from them, and use them in your own classroom. Please feel free to broadcast them in classes or in professional development sessions. You are welcome to download the presentations and modify them as best works for you and your students, including taking just what you need or inserting curriculum-specific examples.
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