We're talking about middle schoolers here, right? I don't care if the kids have been there before or not, if they don't know how to properly behave in public at that age they have no business being there.
That being said I believe a lifetime ban is excessive, though I can recall hearing about whole classes in my area being sent home from field trips for poor behaviour when I was in school and it had nothing to do with them being any color but stupid.
“...instead of considering that maybe the students haven’t been there before.”
I’m sure that any students from this school who haven’t visited the museum are free to purchase a ticket and visit on an individual basis any time they please. Are they so feckless and trifling that they can’t get there under their own steam and on their own dime?
I’ve never been there but I KNOW exactly how to act...
I went to my first opera at this age. With a small (20 or so) group of fellow middle schoolers.
We were all quite well behaved, as we actually WANTED to be there. That does make a difference.