From a practical standpoint, the oldest, and middlest boys are old enough to do many of the things that I do for them, so it's time to step up the responsibility level for them. From now on, if they create a mess, whether it be as a result of foolishness, or as a result of playtime, THEY will clean it up. I almost always have them help clean up after their playtime, but usually in the case of their foolish messes, I administer proper discipline, correction and instruction and then send them to a secure location (their room, the couch etc.) as sort of a time out, while I clean up the unexpected mess.
This is not to say that I am not allowing them to have free time, just not as much of it. I am hoping that they will realize the value of free time, and decide to spend it wisely when they do have it.