Only if they are NOT on a college team. High school athletes working out with college athletes is illegal. Also, he should have a coaching authorization, I believe the word ASSIST is where they get you.
DEFINITIONS: (as per Department of Education memorandum--April 12, 2004)
A coach is a person who holds a coaching authorization or coaching endorsement from the Iowa Board of
Educational Examiners, and who diagnoses, prescribes, evaluates, assists, or directs student learning of an
interscholastic athletic endeavor at a practice session or on the field of competition.
A volunteer coach is a person who holds a coaching authorization or coaching endorsement from the Iowa Board of
Educational Examiners, and who diagnoses, prescribes, evaluates, assists, or directs student learning of an
interscholastic athletic endeavor at a practice session or on the field of competition, but does not receive
compensation from a school or school district for his or her efforts.