ASEP
At the high school where I coach, all coaches whether they are head, assistant, or volunteer have to be ASEP coaching certified. It wasn't tough to get certified but there was a lot of information. If anyone is interested in taking the test or getting information for it, here is the ASEP website.
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Comments
A few years ago I was certified to be an ASEP instructor. Since then, Oregon has changed to NFHS for certification and that is what I use in the PES364 Scientific Basis for Coaching class now. I suggest that people check with the state where they intend to coach before deciding which certification to do. They're both good.