Have a deck of math fact flashcards easily accessible. Have the students form a circle on the rug or open space. Start with two kids standing together, ready for the flashcard. Show the card quickly--the student that answers correctly first continues challenging students around the circle until someone else answers first. Make sure to assign one or two tie-breakers in case there are questions about who answered correctly first. Have a small prize handy for anyone who gets all the way around the circle--Around the World!