The Museum underwent a major refurbishment maybe ten years ago. While I have a lot of nostalgia for the place in the 80's, I'll admit it has never looked better. The crown jewel of the new MOS is the first-floor exhibit, Natural Mysteries:
When I was a teen, MOS had an awesome temporary exhibit called, "What's in Our Attic?" They brought down a bunch of weird things they'd collected over the years, but which weren't on display. Natural Mysteries has nearly all of the items from "Attic" on permanent display. There is an overwhelming amount of cool stuff to look through in displays, in drawers, and even hanging from the ceiling. On top of that, the focus of the exhibit is on the scientific method, classification, and curiosity. In other words, the kids visiting are invited to be scientists.
The Museum appeared to have gone through a refurbishment since the last time I visited about a year ago. This Icthyosaur has always been on the wall, but the plaque and paint is brand new. There are still a few remnants of 70's-ness to be found, however:
I have no idea how old this display is. Still really cool.
The Museum of Science is also an accredited zoo, and live animals are having more and more of a presence. I didn't visit the excellent Butterfly Garden this time, but I did attend a live animal presentation. Opossums! Fluffy little owls!
I'm going to arbitrarily end with this amusing sign, from another special exhibit that was running at the time (Edit - yes, it makes sense in context.):
