This year I received a family annual pass as a gift. I have been several times with my children ages 11 and 13. We have also brought along guests in ages varying from 2 through 7 as we can bring guests for free with the premium pass. It's always been a fun visit. Lots of nice interactive exhibits. Although I was a bit disappointed with our last visit as an unusually high number of exhibits were broken/under repair. We've enjoyed the planetarium shows and have seen three different ones. My children love the Sky Bike, and with the premium annual pass they can ride it for free which is nice.
The best advice I have it to arrive early. We get there when it opens at 9:30 and often when we leave by around noon it's very crowded and not nearly as pleasant as out first hour and a half when the kids can easily get access to the exhibits. On a holiday weekend (Presidents Day weekend, either the Sunday or Monday, I forget) the line to enter was at least 100 people long at noon. But on that same weekend it was close to empty the first hour. Look for street parking. Not only is it cheaper but the facility parking is a bit of a pain to get in and out of.
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