After students have come in having read on some academic topic like the sociocultural foundations of war, have them take a simple pop quiz.
Write one question on the board: for example, “According to the author, is war natural to humans? Why does she think so?” Students must write their answer on a slip of paper and turn it in. They can, once everyone has turned in their papers, discuss their answers with their peers.
This activity not only ensures students have done the reading but also serves as a launching point for discussion of the reading.