Based on the reviews, I did not have high hopes for this sight, but while it was somewhat small and a little expensive, it was great for several reasons. First, the hands-on exhibits were working (with one exception - they didn't have what we needed to a model house). Second, it was in part Miami and South Florida-specific, so there was much to see and experience about hurricanes, about the Everglades biosphere, and the conservation of tropical waters and aquatic life - so it will enhance your kid's (or your own) experience of the rest of your vacation. Third, this museum educated in a fun way. The last science museum we visited (Syracuse, New York) basically said, "here's a Pleistocene-era giant bird" and "aren't these falling billiard balls neat?" while Miami's showed what needed to be done to cancel out an individuals' carbon footprint, why we need to care about the Everglades and the dangers of invasive species, and taught visitors a great deal about energy production (they have the world's only dance floor where the dance energy powers the lights - very nifty).
Note - bring a baseball hat and cover your mouth with it when you're inside the hurricane simulator if you're afraid you won't be able to breathe in 79 mph winds. The two dollars extra to operate the simulator may seem unreasonable (it probably isn't when thinking about how much energy it would consume if it were free), but considering 79 mph is only Category One, you'll gain real understanding for how incredibly powerful bigger hurricanes must be.
This could be a fun two hours, but plan for three if you'd like to also see a planetarium show and the outdoor rescue animals, both of which are included with your ticket.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.