A tech high school machining instructor I know does this and that is how he takes attendance. Almost every kid has a phone...if the phone isn't in the cubby th

A tech high school machining instructor I know does this and that is how he takes attendance. Almost every kid has a phone...if the phone isn't in the cubby they aren't counted as being there. Cabinet locked at beginning of class. There are only 2 students out of his entire year that don't have a phone and he makes allowances for them.