We went last tuesday and it was insane. We forgot it was a free day and we didn't get to watch the video they offer because the times filled up real fast. My suggestion is to wait.
I was there last weekend and I could hardly get through each exhibit. Children were everywhere and there was no stroller control. It was hard to walk through and we got there at 9am when they first opened, hoping to miss the crowds- that was not the case
A free day on summer vacation will be very busy...very.
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