Juliette has lately developed a very strange illness...when it is time to tidy up her arms suddenly become very sore and tired. Uh uh. No way. Tidying up is something I've never let any of my kids get out of. The bathroom can wait five minutes, or we can leave a few minutes late for an appointment, or dinner can be warmed.
I've noticed the same thing when I'm supply teaching at schools. I have a very lax policy on leaving the class. Unless there are strict rules in place by the teacher, I have no problem with kids needing to walk around and stretch their legs (often under the guise of bathroom or water fountain breaks.) I've noticed some kids need to leave frequently throughout the day and there is no way their bladders are that small. More likely is that they are like lions in a cage and those four walls are driving them a little batty. But at the end of the day when it's time to get the classroom back in order, I close and seal the door. Inevitably there are at least a half dozen kids who suddenly have to use the bathroom, and their faces are priceless when I firmly turn them back.
I also get a lot of "but my desk is clean" or "I can't stay after the bell" or "I'm already done my chore." I reply that the door will not open again until the entire class is cleaned up, and if they can't stay then they should help someone else finish. If they are done, they should help someone else. Check the floor, check the desks, check something that still needs doing.
I'm sure it might become a thing I am known for, but that is okay with me.