I have started using them with my upper level English classes and they have been a hit. If you don’t know what minute mysteries are, here is a website to get you started.
I usually give a short statement, then the students can ask me questions until they figure out the answer.
For example: “Joe wants to go home, but he can't go home, because the man in the mask is waiting for him.” (This mystery refers to a baseball game.)
Sometimes there is new vocabulary; other times there is a word the students think they know but has a different meaning in this context. Some of the mysteries refer to something American (like trick or treating on Halloween), so the mystery is way to introduce American culture. The mysteries are fun, educational, and only take a “minute” of our class time!