Score Level 1 Anchor Paper

This response indicates little attempt to apply a reasonable strategy. While the correct answers are provided for both the slope (-5/9) and y-intercept (20), the meaning of slope and the y-intercept in the context of this problem are not given. The answer and explanation for when Tina should replace her tires is also not supplied. The response demonstrates a minimal understanding and analysis of the problem.

Score Level 1 Anchor Paper

This response indicates little attempt to apply a reasonable strategy. A correct answer (-5/9) is given for the slope. The meaning of slope is incomplete; the student needs to include that the slope is how quickly the tire wore down per month. The y-intercept is correct, and the meaning of the y-intercept (the thickness of the tire before it was used) is complete. Both the answer and the explanation for when Tina should replace her tires are incorrect. The response demonstrates a minimal understanding and analysis of the problem.

Score Level 1 Anchor Paper

This response indicates little attempt to apply a reasonable strategy. The correct answers are given for both the slope and the y-intercept; however, the meanings of slope and the y-intercept are not provided. Although the correct answer for when Tina should replace her tires is given, the explanation is incomplete. The response demonstrates a minimal understanding and analysis of the problem.

Score Level 2 Anchor Paper

This response indicates an incomplete application of a reasonable strategy. The correct answer is given for the slope, but the meaning of slope is incomplete. The student needs to include that it is the rate at which the tread is wearing off per month. The y-intercept is correct, and the meaning of y-intercept (the thickness of the tire tread originally) is complete. Although a correct answer (27 months) is given for when Tina should replace her tires, only a partial explanation is provided. The response demonstrates a conceptual understanding and analysis of the problem.

Score Level 2 Anchor Paper

This response indicates an incomplete application of a reasonable strategy. The correct answer is given for slope, and the meaning of slope (how much the tire tread wears in a month) is complete. The correct answer is provided for the y-intercept, and the meaning of y-intercept (how thick the tire was from the start) is complete. The answer for when Tina should replace her tires is incorrect; however, the explanation, substituting 5 for y, would support a correct answer. The response demonstrates a conceptual understanding and analysis of the problem.

Score Level 3 Anchor Paper

This response indicates application of a reasonable strategy that leads to a correct solution in the context of the problem. The correct answer (-5/9) is given for the slope, and the meaning of slope (the amount the thickness of the tire tread decreases per month) is complete. The correct answer (20) is provided for the y-intercept. The meaning of the y-intercept (the initial thickness of the tire tread) is complete. The correct answer (27 months) is given for when Tina should replace her tires, and the explanation, substituting 5 for y, is fully developed and supports the solution. The response demonstrates a complete understanding and analysis of the problem.

Score Level 3 Anchor Paper

This response indicates application of a reasonable strategy that leads to a correct solution in the context of the problem. The correct answer (-5/9) is given for the slope. The meaning of slope (how much the tire tread wears down each month) is complete. The correct answer (20) is supplied for the y-intercept, and the meaning of the y-intercept (the starting thickness of the tire tread) is complete. The correct answer (27 months) is given for when Tina should replace her tires. The explanation, substituting 5 for y, is fully developed and supports the solution. The response demonstrates a complete understanding and analysis of the problem.