Subject: Math
Grade: 4-8
Objectives:TWL:
1. Assign values to a variable.
2. Collect information about variables and be able to use the information to solve for an unknown variable.
Materials Needed:
For each group of three students:
1. 8 small containers
2. 80 small countable objects
3. code sheet prepared by the teacher
SET:
Expain to the students that they will play a game where they will try to solve other team's "Secret Numbers".
Review:
Go over solving equations. Ensure everyone remembers how to solve equations. Explain that they will learn how to write equations with this game.
Procedure:
1. Divide the class into groups of three. Distribute 8 containers and 80 counters to groups. Instruct each group to elect a recorder.
2. Each group is assigned a different letter of the alphabet. Have students label their 8 containers with the lower case letter.
3. Each group chooses a " Secret Number". They tell only the teacher, who records each one on the code sheet.
4. Have each group place the secret number of counters in each container.
5. Each group now has 8 containers, each with the same number of counters and the same letter of the alphabet. Discuss ways to express the total number of counters in all 8 containers. For example, X+X+X+X+X+X+X or M+M+M+M+M+M+M. Build on that idea: 7X or 7M.
6. Have groups exchange containers with one other group. For example, 3X's are traded for 3M's. Each group records its holdings like this: X+X+X+X+M+M+M or M+M+M+M+X+X+X.
7. Each group confers with the teacher to check exactly how many counters they are holding. For example, the first group has 4X + 3M counters. The teacher tells them they have 24 counters.
8. Discuss how to write the equation 4X + 3M = 24 to express the number of counters.
9. Have each group solve the equation for the UNKNOWN variable.
10. Students continue to trade until all the secret numbers are dicovered or until time runs out.
11. Encourage groups to keep their solutions to themselves to ensure each group makes discoveries on their own.
Closure:
Have students return to their desks. Discuss how they should now be familiar with writing algebraic expressions to represent real numbers.
Assessment:
Students will be assessed informally as well as on a written test.