An Introduction to Open Licensing and Creative Commons in the context of U.S. Copyright
For most people understanding U.S. Copyright law is challenging and often frustrating. The complexities of understanding your rights as a copyright owner, as a user of third-party works, even as an educator, and especially in a digital environment take time and effort. Laws pertaining to copyright changes over time, and the purpose of copyright "to promote the progress of science and the useful arts" (I U.S. Constitution S8, c8) sometimes seems lost, especially for those who are not legal experts.
While extremely specific use exemptions exist for classroom teaching, libraries, and online learning exist (see "Copyright in Teaching"), fair use analyses are still an option, and obtaining permission (and sometimes paying a fee) are also options, the advent of authors applying Creative Commons licenses to their works has greatly broadened the availability of creative, original works which may be used with attribution as designated by their authors.
MERLOT is a curated collection of free and open online teaching, learning, and faculty development services contributed and used by an international education community. MERLOT is a program of the California State University System partnering with education institutions, professional societies, and industry. New user registration Contribute material
OpenStax CNX "Connexions" is a free, open platform developed at Rice University for development, editing, and mashup of openly licensed content. The content in OpenStax CNX comes in two formats: modules, which are like small "knowledge chunks," and collections, which are groups of modules structured into books or course notes, or for other uses. New user registration Login to contribute material
There are many other disciplinary and institutional repositories and "referatories" which aim to collect, curate, and enable ease in finding openly licensed resources. Ask your disciplinary societies if such a repository exists for your subject area.
You may also want to make certain that you mark your work. Include author and license information, and make sure that the license on your work is machine readable (easy; technical) so search engines with "usage rights" filters can find them. (For example: Google Advanced Search offers filtering by "usage rights".)