Sash was a big Komsomol guy in the 80s. He had to may up at 6 am on May Day to carry Lenin placards. "It sucked!" He has a Lenin prize for trying to reform the Komsomol. "The Komsomol was not about ideology! It was about hanging out, drinking vodka, listening to Pink Floyd and meeting girls!" I find everyday Soviet life to be fascinating.
My description will be very approximate. I've seen only one museum of atheism. It occupied a beautiful 19th century mansion on Volodarsky street in the center of Moscow, not far from metro station Taganskaya. The first floor accommodated an exhibition of books on atheism by Soviet writers, basically critical analyses of the Bible. Also, some exhibits on history of religion, particularly pictures of Russian pagan gods. Also placard, posters and funny cartoons of anti-religious content drawn in different years after 1917. For example, fat piests telling lean and hungry peasants to "share fairly" The second floor accommodated a theater for lectures, seminars and documentary film shows. Lectures and film shows took place regularly, but not every day.