I have been playing Monopoly since before 1950.
Aside from the fun, it provides one of the best ways to introduce the idea of marginal to an intro economics class; and because I’m not teaching my giant section of intro microeconomics this year (the first time since 1980/1981), I miss both teaching and Monopoly.
Each Monopoly property gives a payoff when an opponent lands, with the payoff rising from double the rent if you have a monopoly with no houses, up to a maximum total return with a hotel (five houses).
On a given property, each house costs the same; for example, on New York Avenue, my favorite property, a house is $100. But the marginal return to a house is not constant: it rises steadily with the first, second, and third houses and then falls with the fourth and fifth.
This dictates strategy: if you have two monopolies and limited resources, even though the big red hotels are pretty, you are better off building equal numbers of houses on both monopolies, rather than hotels on one and nothing on the other.
Here’s one other economics lesson that is well known to Monopoly veterans: better a monopoly on the farther end of each side of the board; the houses cost the same on each side, but the payoffs at the farther end are greater.