Parents, start here. Get an EZSKI for kids who are hesitant to try waterskiing. Kids can pretend that they are water skiing by sitting on this tube in your living room. Little by little, they will build confidence and put the tube in the water. They do not have to get in the water, especially when the water is cold. After a gentle sit down ride, it is not long before the stand up. This has a Zero learning curve and the ride is very stable.
The next level is a pair of waterski trainers. These trainers have a bar that hooks the waterskis together and makes for easy starts. When you child has mastered riding a trainer, remove the bar and the kid will get up like a pro on a pair of water skis.