USER LICENSE:

By using these materials, we are asking you to participate in a curriculum development project by agreeing to do the items below.

We base our license on the Creative Commons Attribution-Noncommercial-Share Alike 3.0 License modified to include a share-back criterion:

Our modification of "share-back" includes that you agree to:

• send David Maloney or Mark Masters an email telling us that you are using the materials.
  Refer to the contact information at the bottom of the page for addresses. In your email, be as specific as possible about which materials you have used (or plan to use) in your class and give us a report on what you did (if possible). This is extremely important to us as we modify materials to be most appropriate for users.
• "re-publish" any modifications you make by sending them back to us (via email...).
  We will update our materials if needed, or we will publish your version in parallel here online. It helps to have descriptions of the modifications so that future users can gain insight into your work.
• any and all comments about the activity and your experiences with it.

By agreeing to the user license, you are helping us in our curriculum development and ensuring that high quality materials are created. We retain all publication rights to these materials, but are happy to share them as broadly as possible.