Structure is vital to all children, even during their summer school break. As parents we struggle with the notion of our little darlings having no down time to just be kids. But letting them sleep in until noon just because school is out is not a good plan either. Sure summer time should about fun for everyone, but just like adults need to have a balance so they can work and do other necessary things such as housework, so too a kid needs balance as well.
Athletes, are perhaps, the best example. They are usually have the busiest schedules, even during the summer time, they are usually excellent time managers and they usually make up 90% of the honor role. Do they have time to play? Of course they do. And they usually do it while maintaining balance.