How much stuff are your kids involved in?
Mine just has a fitness class one day a week.
There is a mom whos kid is in my son's class at school and last Spring she told me that he was in:
ALL AT THE SAME TIME.
There were five weeks straiight when soccer, basebal, and basketball were all going on at the same time and they coordinated the practices, as most of the kids were all on the same teams.