Incorporating the Kagan Structure, Mix-N-Match, is the perfect way to practice subtraction facts. Cut out an laminate the cards. Students will get up and mill around the classroom trading cards with other students as they pass by. The teacher calls "freeze" and they stop. When the teacher calls "match" students actively seek out the partner that has their matching card. Enjoy this free preview. A class set of cards is available for purchase at my store.