What Makes A Mystery?

I started writing children's stories about dogs and cats when our writers' group challenged its members to write mysteries. We came up with a neat short template for the creation of a "quick" mystery:
At number one, write down who is going to misunderstand something.At number five, write down the dire consequence of the misunderstanding.At number seven, write down the resolution – all is calm, mystery solved, misunderstanding corrected.Back to number three: What did your protagonist misun...