It sure is , I first went with school odd at it sounds now we just got let lose to wonder round on our own. Me and Mrs 73 have been round since but not since the last revamp when they moved the blue whale into the main hall.
Have to admit, I like museums. One of my faves is the japanese gallery in the British.
The Museum of London is also wort a visit, though IIRC they've now moved, expanded and are at multiple sites. But BITD it was in the Barbican, and I went to school more or less next door, and so we went there regularly as part of history lessons.
I'm planning on re-visiting the British Motor Museum at Gaydon. I judged at a cat show there a little while back, and didn't have much time to look at any of the exhibits, so I want to go back and take my time. I also want to book some time in their archives to see if I can find out more about my Mini, as they have most of the production records.