How about giving them something to strive for? When i was a kid, I could perform all the athletic tests at the highest level except I couldn't do 2 pullups, so I got nothing. It pissed me off, and it motivated me to train myself to do pullups. My Dad gave me some training tips and the next year I was able to do more than the minimum of 2. I did enough to reach the highest award level. I think it was 7 to reach what they called it the Presidential level. I can still remember the pride that I felt from overcoming that hurdle. If I got an award without doing the pullups, I never would have pushed myself.