Even though it is in Hartford, it is only a 25 minutes drive from New Haven. It is a great museum, for both big and small kids.
As soon as you get in, there is a large water room that you can get wet. Kids love this room. Nearby there is a 4-D theater. Going upstairs, there are all sorts of things for you to play and learn. On the third floor it has a whole Space and Universe room. You can experience being an astronaut, and see all the things that you’d find in the outer space. On the fourth floor sometimes there are special exhibits. You can find more details from their website.