Play this game with the entire group of students. Create a set of cards, making sure you have enough for each student to get at least one card. Choose a student to read his card orally: “I have 10. Who has the least common denominator for six and five?” The student holding the correct response reads next: “I have 30. Who has the least common denominator for two and nine?” Each student reads his card, as play eventually loops back to the first reader.
Divide students into pairs. Give each person three six-sided dice. The students roll the dice at the same time and determine the least common denominator for the three numbers they roll. The player with the greatest common denominator scores a point. The winner is the person who first scores 20 points. Give each pair a list of multiples to use as a checklist when there are disputes.
Purchase decahedron dice — 10 sides numbered zero to nine — from a teacher’s supply store. Students work in pairs. Each player takes a turn rolling two dice and determining the least common denominator for the rolled numbers. Players score one point for each correct answer. Give each group a list of multiples for zero through nine to use as a checklist when there are disputes. Play continues for 10 rounds, and the winner is the student with the highest score.
This arcade-style online game by Sheppard Software has three ability levels and two formats: relaxed, in which the student completes 10 problems at his own pace; and timed, in which the student has one minute to complete as many problems as possible. Two fractions, such as 2/3 and 5/7, appear on the screen. Least common denominator choices float on the screen in different-sized fruits. The user clicks on the correct answer. He receives a score at the end of the game.
Divide students into groups of two or three players. Give each group a standard deck of playing cards and instruct them to remove face cards. The cards are evenly distributed. Players turn their stacks over so the numbers aren’t visible. They simultaneously turn over the top cards in their stacks and place them in the middle. The first person to correctly state the least common denominator for the numbers in the middle picks up the cards. After a set amount of time, the person who has accumulated the most cards wins.
Divide students into two teams. One player from each team goes to the board. Give them a problem to solve — addition or subtraction of fractions, requiring a common denominator. The first person with the correct answer scores 10 points; the second person with the correct answer scores five points. If a student needs help, he can ask a team member to join him. The team member gives advice, but doesn’t write on the board. Deduct two points when the player uses a helper. The team scoring the most points in a set time frame wins.