You have to have either 60- 80 college hours to be on the field to coach regardless of head or asst. You do not have to be a teacher to be a head coach. Pretty much if they cannot find someone in house or in the system to be a head coach they go outside to find someone - it's left up to the system as to what they do.
Other than that it really doesn't matter and a school does not have to post coaching openings like they do teaching.
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