There are several standard activities that I have used over the years that have made my teaching interesting, at least to me. There is nothing better than a good joke to jump start the thinking process, especially when the joke comes in the middle of an explanation.
Jokes require imagination.
They produce subtle, mental twists. They prepare the listener up for the unexpected. Telling jokes is precisely going from what the learner knows to what he doesn't know. He doesn't know the punch line. Your mother has a terrible, strained look on her face.