I popped into the Cultural Museum Mandalay basically because I was passing. It is supposed to be one of the places covered by the 10USD "combination ticket" but I wasn't asked for one - I didn't have one (see seperate tip). Please note that the entry fee on the Government website provided is incorrect.
Had I been asked to pay, I would have felt myself seriously ripped off, there is just nothing here. The guy on duty didn't seem the least bit interested and waved vaguely towards a large room that resembled an abandoned old-fashioned railway waiting room. There were a few exhibits in cases, few of which were annotated. Another couple of rooms in much the same vein followed. The best room was a small room at the back of the building where there was an old cart and some old implements. Unfortunately, the gloom of the place (the lights weren't on) made it difficult to see anything.
Unless you've got a specific exhibit you want to see for research or something, I really wouldn't bother.