Great story. I have had the great opportunity to take a few young/new hunters out. I try to simplify shooting as much as possible. I have all my rifles set up using a 'Maximum Point Blank Range Calculator' or MPBR. All we have to do is get the range of the target and as long as it is not past the MPBR they can aim for the vitals and pull the trigger. No holdover or fiddling with turrets. Congrats on a successful hunt. You made some memories those boys will never forgot.
P.S. The first morning of my son's bull hunt last year we hiked about a half mile in before we realized that neither of us had brought the rifle. Good thing he runs cross country as well.