Private Clubs: line up all the junior-age children of members one night a week and say "we're going to these two holes, to the drive zone, and we're going to play with sand." Every two months, you get some coverage. If you have enough kids, make it three. For high-end clubs, you have a ground crew that you pay super well, so ignore.
Public courses: find the junior golfers that frequent your course and say "hey, for every week that you come out on Thursday evening, we will give you a free chit for golf. If you cover 2 holes, we will give you a 9-hole chit. If you cover 4 holes, we will give you an 18-hole chit."
In both cases, you could also assign the kids to putting greens on the course and, as soon as they clear and no one is hitting in, the kids swarm the green (gently, in sneakers, no running) and fix all the ball marks. If you have enough carts/gators, you can get the kids around the golf course promptly.