Teacher here. Anyone who works with teens knows the overwhelming power of peer pressure. Then stir in the potential disapproval of an authority figure, especially if it is one you respect. Top it off with the fear you might lose your starting position or fall even further out of favor with the coach. Few teens could withstand all that.

Anyone who thinks these prayer sessions is voluntary with no coercion knows nothing about teens and has forgotten their own teenage years or - as in the case with the SCOTUS - willful liars and hypocrites.