Grades: 4‒8

This activity features three games. In the first two games, students deduce the numerical values of ten variables, *A* through *J*. Through experimentation, students discover an “add one more” strategy for determining the values of each variable (e.g., If *A* + *B* = 10 and *A* + *B* + *C* = 13, then *C* = 3.) In the third game, the variables move in random patterns across the screen. Students need to quickly find the sums of groups of variables before they move away from each other or cross to the opposite sides of the screen.

OBJECTIVES

- Students will use logical reasoning skills to determine the secret numerical values assigned to variables.
- Students will develop, refine, and share intuitive strategies for solving algebraic equations without formal symbol manipulation.

COMMON CORE CONNECTIONS

Mathematical Practices

(1) Make sense of problems and persevere in solving them; (2) Reason abstractly and quantitatively; (3) Construct viable arguments and critique the reasoning of others; (5) Use appropriate tools strategically; (7) Look for and make use of structure.

Content Standards

6.EE2, 5, 6; 7.EE4; 8.EE8

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