Are the Odds in Your Favor?

Using the attached Lesson Slides, show students the guiding questions on slide 3: What are the odds of winning at games of chance? What impact does gambling have on people and society? Ask students to consider these questions throughout the lesson. Move to slide 4 and briefly introduce students to the lesson objective on the slide.

Go to slide 5 and explain to students the rules for the Eleven Game. Divide students into groups of three. Ask each group to designate one scorekeeper (the two remaining students should act as players). Pass one a copy of the attached The Eleven Game Score Sheet to each group. This score sheet contains the rules of the game and a score sheet for the scorekeeper's use. Additionally, pass out three dice to each group.

Remind scorekeepers to count the total number of times that the dice are rolled by each person, regardless of whether they roll an 11 or not. This is recorded on the scoresheet.

Have groups play. As students begin to reach scores of 99, move to slide 6. When a student from a group wins, have the group's scorekeeper do the following math:

1. Count the number of times each player rolled the dice, regardless of whether they won the roll. For example, the winning player's total rolls will equal more than 9. This number should be the same or nearly the same for both players.

2. Next, record the number of times each player scored the winning number 11. For example, the winning player will have rolled exactly 9 winning rolls; a losing player with a score of 44 will have rolled 4 winning rolls; and so on.

3. For each player, write the ratio of the winning rolls to the number of total rolls. This ratio should look like a fraction. Use the number of winning rolls for the numerator, and the number of total rolls as the denominator. For example, if the winning player had 9 winning rolls out of a total of 15 total rolls, their ratio would be 9/15, which reduces down to 3/5. If the losing player had 4 winning rolls out of a total of 15 rolls, their ratio would be 4/15.

4. Change each fraction into a percentage by dividing the numerator by the denominator. For example, the fraction of 3/5 would equal 60%. The fraction of 4/15 would equal 26%.

Once all scorekeepers have done so, move to slide 7. Create two columns on a poster or whiteboard space, labeling these, "Winning Percentages" and "Losing Percentages" as shown on the slide. Invite each scorekeeper to come up and record both the winning and the losing players' percentages in their respective columns to display for the class. Explain to the class that this game (rolling the dice to get an 11) is purely a game of chance, not of skill.