This is an excellent museum and gives an excellent detailed overview of communism in Czechoslovakia. It covers the rise of the communist workers party and its applicable history to Czechoslovakia .
There are many wall mounted written panels and to get the best out of the museum theses must be read so probably not a good option for younger children.
It costs 380 CZK for an entrance ticket.
The main floor has subject areas based on Communism -The Dream(The birth of Czechoslovakia, Munich Agreement, Victorious February.)
Reality (Nationalization, Communist Propaganda, The Socialist shop, The secret police.)
The Nightmare (Political trials ,Labor camps, August 1968-occupation, the velvet revolution). The information was well supported by artefacts from the period. Especially the reconstruction of an Interrrogation room
I visited just before Christmas and the Cafe was closed and the souvenir shop was very limited in the items it was selling.
All in all an excellent museum and a must see if in Prague.