WISC Online, a project of the Wisconsin Technical College System, hosts a collection of open learning objects -- activities, videos, and more -- that can be incorporated into your courses. They have several categories of materials including Math, Manufacturing & Engineering, and Science.
Line E: Electrical Fundamentals Competency E-1: Describe the Basic Principles of Electricity
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Introduction to Programming Using Java, Seventh Edition
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No calculator? No problem. Desmos can do what an expensive graphing and scientific calculators can, for free.
Check out the Desmos Getting Started page or check out their video tutorials or user manual.
Indian River State College has assembled an excellent list of sources of free to use or openly licensed images and videos for science OER:
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