Use randomized assigned seating for midterms.
Many classrooms have labelled seating; this makes it easier to assign students to random seating. The procedure is easy to implement by posting students' IDs and assigned seats outside the classroom shortly before the exam or possibly displaying them on the overhead projector as students enter the classroom. Another approach is to hand out tickets with seat numbers as students enter the room. Students seated next to strangers are less likely to cheat. Once students are seated, the invigilators use copies of the plan to verify that students are in their assigned seats.