We think of God and heaven as a place where our Supreme Lord has everything ordered. Perfectly ordered. A machine with gears and cogs that run for infinity without any required maintenance. A utopia, where there is no need for improvement.
According to Spiritism, earth is an imperfect representation of heaven. From this, we are to understand that there are organizations, learning centers, work, architecture, etc., all of the required components that we need on earth to run a large city or a nation which also play a role in heaven.