This is really challenging.
The thing that has helped us the most is a change that we made last year. I had really mixed feelings about changing, but chambero here on Steer Planet assured me it wouldn't effect the hair growing and he was absolutely right.
We started rinsing once a day. If there are games at night, we rinse in the morning. If there is nothing going on that night, we will rinse at night. This one thing helped manage all of the activities more than anything.
To be honest, we actually had BETTER hair than we have ever had. I know that every summer is different and every calf has different hair. I believe that the skin was healthier, and that made a big difference.
What grows hair more than anything is cool and dark. Sure we work their hair, but I believe getting them into the cooler where it is dark, and having high velocity air blowing on them really helps the process along.
I know it is hard to manage all of the activities. Just do your best, and enjoy the time that you have with your kids.
I was sitting at a basketball game the other night, and overheard a couple parents whining about running all the time. They were bitching about the demands put on their kids due to sports, and bitching about the coaches, and someone else's kid not deserving to be on the court...you know, the usual. I knew the people, and they asked me how I managed to do all of it all these years. I turned to them, and told them how I felt about it. I told them that I would give anything in the world to watch my two older boys that have graduated from high school run out of that tunnel and onto the basketball court just one more time. I told them to cherish every single minute of it. When it is over, it is over...and you never get it back.
You will figure out how to get hair on them, and get all of the other stuff handled as well. We show cattle. It is what we do. It is what makes all of us unique. The very fact that you are asking for tips and advice is proof that you have what it takes to get it all done!
I compliment you for taking all of it on!
Good luck with the calves and the sports!