roll call

I call roll in every class at every level. To get students thinking in English, I ask them to answer their name with some English word. Beginners must name a food or color or animal or some similar broad but deffinite category. More advanced students "graduate" to emotions, English last names, Pop singers--anything that will have enough different items to cover the class because items may only be used Once. Usually I tell the class the day before as part of their homework that they will have to review or research such-and-such a category for the following day.
Sometimes a discussion develops about an item used by a student, and sometimes the category of the day leads into the grammar or listening or whatever lesson (whaddyano!)