We popped in briefly before closing for the first time on a holiday when most museums offered free admission (MLK Day, if I'm not mistaken). I did not expect there to be live animals outside, which was very cool! We quickly walked about half of the first floor just to get a lay of the land and get a sense of what kind of exhibits there were. Having only had time to see a few staples, the animals, and the Planetarium show schedules, We were more than satisfied and decided soon after to become members. In the last few months, we have been back a few times. During those visits, we have seen 2 different shows in the planetarium and explored the basement area for kids. We also came for a Think and Drink event (murder mystery the time we went), which was actually pretty legit! I was pleasantly surprised and glad that we joined the museum.
Tip: Not only do you recoup the cost of membership with just 2 visits, but there is reciprocity with a lot of establishments (see website for more details). We took advantage of this on a recent trip to NYC/NJ by going to the Intrepid Museum in Manhattan and to the Liberty Science Center on the other side of the river.