Look at quadrilateral KLMN.

Step A
What is the measure of ∠M?
______________degrees
Step B
- Use what you know about the angle measures of a quadrilateral to justify why the measure you determined for
M is correct. Use words, numbers, and/or symbols in your justification.
- A new quadrilateral KLMN is drawn so that the measures of ∠K and ∠L do not change, but
M and ∠N are now congruent. Use what you know about the angles of a quadrilateral to explain how this change affects the measure of ∠M. Use words, numbers, and/or symbols in your explanation.
Step A is scored 0 (Incorrect) or 1 (Correct) and assesses 2.A.2.a.
Step B is scored with a 4 point (0, 1, 2, 3) rubric and assesses Processes of Mathematics.
Note: 6 "Sample Student Responses" follow below. Each response appears on its own separate page and includes scoring information. The "Sample Student Responses" represent a range of score points.
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| Correct Answer |
rubric. A new quadrilateral KLMN is drawn so that the measures of ∠K and ∠L do not change, but M and ∠N are now congruent. Use what you know about the angles of a quadrilateral to explain how this change affects the measure of ∠M. Use words, numbers, and/or symbols in your explanation. |
| Sample Student Response #1 |

Score for Sample Student Response #1:
Step A -
Content (Knowledge of Geometry): 0
Step B -
Processes of Mathematics: 1
Annotation for Step B, Using the Rubric: The response demonstrates a minimal understanding and analysis of the
problem. Instead of a justification for why the measure of M is correct, the response
provides the start of an explanation ("add all of the angles together to get 292° ") for how to
determine the measure of M . The explanation for how the change affects the measure of
M is missing.
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| Sample Student Response #2 |

Score for Sample Student Response #2:
Step A -
Content (Knowledge of Geometry): 1
Step B -
Processes of Mathematics: 1
Annotation for Step B, Using the Rubric: The response demonstrates a minimal understanding and analysis of the
problem. Instead of a justification for why the measure of M is correct, the response
provides an explanation ("you have to add all the other angles up the subtract the total
from 360° ") for how to determine the measure of M . The explanation for how the change
affects the measure of M is missing.
|
| Sample Student Response #3 |

Score for Sample Student Response #3:
Step A -
Content (Knowledge of Geometry): 0
Step B -
Processes of Mathematics: 2
Annotation for Step B, Using the Rubric: The response demonstrates a general understanding and analysis of the problem.
Instead of a justification for why the measure of M is correct, the response provides an
explanation ("I added 98 + 82 + 112 = 203 and 360 minus 203 is 157") for how to determine
the measure of M . The minor addition mistake does not detract from the process used by
the student. A complete explanation for how the change affects the measure of M ("then
M and ∠N would be 75 degrees") is provided.
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| Sample Student Response #4 |

Score for Sample Student Response #4:
Step A -
Content (Knowledge of Geometry): 1
Step B -
Processes of Mathematics: 2
Annotation for Step B, Using the Rubric: The response demonstrates a general understanding and analysis of the
problem. Instead of a justification for why the measure of M is correct, the response
provides an explanation ("I first added all the sides together then subtracted 360 − 292") for
how to determine the measure of M . A complete explanation for how the change affects
the measure of M (" M and N would have to be 75° ") is provided by giving the new
measure of M .
|
| Sample Student Response #5 |


Score for Sample Student Response #5:
Step A -
Content (Knowledge of Geometry): 0
Step B -
Processes of Mathematics: 3
Annotation for Step B, Using the Rubric: The response demonstrates a comprehensive understanding and analysis of the
problem. A complete justification for why the measure of M is correct ("all the angles in a
quadrillateral add up to 360° ; First I added the angles K + L, N up and got 292° . Then, I
subtracted 292 from 360° and got 108° ") is provided. The minor subtraction error does not
detract from the completeness of the justification. A complete explanation for how the
change affects the measure of M ("they both would be 75° degrees") is provided by giving
the new measure of M .
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| Sample Student Response #6 |

Score for Sample Student Response #6:
Step A -
Content (Knowledge of Geometry): 1
Step B -
Processes of Mathematics: 3
Annotation for Step B, Using the Rubric: The response demonstrates a comprehensive understanding and analysis of the
problem. A complete justification for why the measure of M is correct ("all four angles of
a quadrilateral must have a sum of 360° ;98° +112°+82° = 292° , not 360° so 68° was
needed. 292° + 68° = 360° ") is provided. A complete explanation for how the change
affects the measure of M ("they both will have 75° angles") is provided by giving the new
measure of M .
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