I can't think of what to do!! How many times to do you hear this on in class. I have been doing some AVID training and learned an activity called take one, give one. This is how I adapted the activity for my art class.
I showed my students step by steps for zentangles. I took about 45 minutes to do so. With the last 15 minutes of class I asked my students to create their own. When they came into class the next day they were asked to get in groups of two. I asked them to take one, give one. In other words. They had to teach their partner how to create their zentangle and they learned a design from their partner. I had them create these on post it notes. They took and gave three times, each time putting their work on the back cabinets
By the time it was the end of the day, we had more ideas then one could imagine. I left these up throughout the week that they were working on Zentangles to help my students generate ideas. It was a real success!