I did this for a regular class and for over 2 hours in a camp. It works really well and it gets the students speaking. I was going to make a small video showing what I wanted the students to do but I didn't get around to do it. The idea is basic, one student starts reading the script and then pulls out a topic from a hat/basket and then a second student has to speak for 1 minute on the topic. The first student cannot stray from the script and must speak it exactly. I found this works well and you can reuse topics as it will be a different student the next time around. In both classes the kids were terrified but after the first round, they got used to it and started doing better and better. I couldn't believe how well this worked. Also, I let the students go and speak about anything as long as it was in English and related to the topic. I also added time for long pauses. I wanted 1 full minute of speaking.