For our speaking class final exam Zhao Laoshi had us talk on a subject. Ten minutes before our exam we were given our topic. I drew sports. One of the questions we were to address in our topic was "What is your favorite sport?" so in the course of my final I told Zhao Laoshi that tai chi was my favorite sport and that I had practiced it for over 30 years.
At class the next day Zhao Laoshi started talking about the exam and how everyone did. I didn't realize it at the time of the test but she was taking notes on what everyone said. When she mentioned my exam she told the class I practiced tai chi and asked me to come to the front of the room to demonstrate.
I didn't realize it at the time but fellow student Xiang Siow made a video. He recently posted it on youtube. Click the link if you would like to see it.