This was a highlight of my recent trip to Montreal! Exceptionally cold weather forced my friend and me inside for the majority of our trip. It was too cold to stay outside for too long, so we found indoor activities between short spurts sightseeing outdoors.
The archaeology museum is quite interesting, with a number of exhibits that range from Native American history of the region to an exhibity on the national Canadian pasttime: Hockey!
The newer addition of the museum houses a sewer (which was actually really cool!) And the archaeological site which has been excavated. The interactive displays are beautiful and worth more time than we actually spent there.
Overall, the museum was a positive surprise and I would highly recommend it to all visiting Montreal. There is even a cool kid-friendly zone so the kids wont be bored either. They can explore the life of a privateer aboard old-timey ships.