Last month we took advantage of a free day at the museum. We had a ball. The kids really enjoyed the exhibit. My favorite was the dangerous snake exhibit. I am not a fan of snakes but I do like looking at them when they are behind thick glass.
This was a very frugal field trip for us. The admission into the museum was all free. We drove 40 miles which really was not that much for us and we packed our own lunch. The whole day cost us just $7.00 for a family of 5.