David Brin mentioned this idea (that Earth may be weirdly dry compared to most life-bearing worlds) briefly in "The Great Silence", published Sep 1983 in the Quarterly Journal of the Royal Astronomical Society. If true, maybe many intelligent species never develop much tool use, or even conceive of radio or interstellar travel.
I used to work at the Franklin Institute, so my recommendations are based on that. I'd like to say that while I love the American Museum of Natural History in New York, it doesn't have the same kind of interactivity. The Exploratorium in San Francisco does, although I don't remember it being as large at the Franklin Institute. It did have some very cool unique exhibits I hadn't seen elsewhere. I quite liked the Boston Museum of Science - very similar to the Franklin Institute in many ways, so your husband may like it a lot. The Liberty Science Center in New Jersey was opened by ex-Franklin Instituters, I believe, but the last time I went (admittedly, something like nine years ago), many of the exhibits were in terrible disrepair.