Most of the ones we saw looked accessible. There are elevators that provide access to all the floors.
Not sure that I know the answer to that question completely, but the rooms are used for actual classes so I would imagine that they would have to be ADA compliant. I remember from my trip that they were all on the same level as the hallway so I would imagine they would be.
Yes, as there are elevators to get to the nationality rooms which are on the 1-4 floors. Some of the rooms are small with chairs and tables, so you will be able to look in or even get into the rooms for a better look. There are some stairs on the floors, so you may have to backtrack to get to all the rooms. The nationality rooms are in a big circle, from these Floors you can overlook the beautiful entrance to the Cathedral of learning. Take your camera. The rooms are all very unique and decorated with amazing detail.
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