Q: When does it rain money?
A: When there is change in the weather!

Explanation: “The rain in Spain falls mainly on the plain,” according to the song from My Fair Lady.   In Peru, they just wish it would rain!  But nowhere does it rain money.  Rain is water that falls from the sky as part of the evaporation/water cycle.  When it is sunny outside, and then the weather changes to cloudy or rainy, we say that there is a change in the weather.

Change is also the word used for money in the form of coins.  In the United States, change includes pennies, nickels, dimes, quarters, and half dollars.  There are also dollar coins.

This joke is funny because it plays with two meanings of the word change: coin money, or when one thing becomes different, like the weather changes. If there were change, coins, in the weather, well, there might be coins falling from the sky, but we all know that doesn’t happen.

John Fogerty sang about change in the weather-