It sound like they are bored. And sounds like detention person needed a break from them.
Sounds like even as exasperated as you are with them, you are nicer to them than the detention person.
This is a team problem that requires a team approach. Did you keep statitistics on how often they came, the reason and what they did? Did you share the information with your supervisor?
Who is monitoring the detention room?
Not sure how the parents can help with this? Sounds like a school issue.
Write it up. 1 page, just the facts. Who, how often, describe impact on the health office and the children who are sick. Don't guess about the cause. Have several trusted friend read it and make sure no emotion, no blaming. Don't just send it, ask for a meeting to discuss with supervisor. If the supervisor does not suggest it, ask for a meeting with the team to plan a behavior plan for the kids. Ask for some training, perhaps with the counselors, or readings on strategies for responding to children with problem behaviors. You need a game plan on how to respond.
One link which might help:
http://www.aacap.org/cs/root/facts_f...fiant_disorder