We went last weekend, for the Festival of Chocolate. They wanted $22 for each of the adults regular admission, and $18 for my two year old grandson, so I just went ahead and bought the family pass, with the IMAX, which got us $10 admission to the Festival, with my grandson being free. The Festival, which is one of their biggest events, was so-so...certainly not worth the $22 fee, and barely worth the $10 fee, because everything there costs more money! (They make you buy "coins" for $1 each, and then things are priced in "coins" - as in a chocolate covered strawberry is 4 coins and a cupcake is 5 coins....not cheap...). We went into some of the museum exhibits, and they were not appropriate or interesting for the two year old. We will visit some of the IMAX movies, and see how he tolerates those, but I probably wouldn't purchase that add-on next time. We will also probably come back and visit the bouncy house thing - although I believe it costs money over and above the museum admission as well.
The only reason I did the family membership was because of some of the reciprocal perks - there is a list on the membership page - like Sunken Gardens in March etc.
MOSI really needs to tear down the exhibits one by one and retrofit them, with more interactive explanations, and things for the younger kids. I feel like they are geared towards school field trips, with guides, and bus parking, and not towards individuals.
Parking was horrible - not sure if it was just for the Festival or not, but we had to park very far away in an un-mowed field, and had to travel through the sand pits to get there - with a stroller. There were no sidewalks, and we were DIRECTED to walk on the grass to get to the entrance they wanted us to use - no way around it. And we were trying to exit the parking lot with the stroller, and the only paved area was the place where the barriers went up and down, and cars were coming in that same place - very dangerous, very poorly designed.
And for a facility that is supposed to be for children, why the single tiny elevator for three floors? Holds maybe two strollers at a time? We carried the stroller down a flight of steps rather than stand in that line again....again, bussing in field trips, rather than a family that includes a smaller child.
So - we will return, for an IMAX movie and a bouncy thing, to get our money's worth from the membership, but I seriously doubt this will be a multi-year thing.
If you are a tourist? Nah, don't bother.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.