Figure ABCDEFG  below is to be reflected over line to form figure A'B'C'D'E'F'. Complete the following on a piece of paper and/or in the answer box below: Draw the reflection of the figure over line .   Explain the steps you used to draw the reflection of the figure.   Explain the relationship of the distance between line and point D to the distance between line and point D'.

The following 6 Anchor Papers represent a range of score points and are used in conjunction with the rubrics to assess student responses.

Score for Anchor Paper #1: Rubric Score 1

Annotation: This response demonstrates a minimal understanding and analysis of the problem. The representation of the reflection resembles the original shape to be reflected and has three points (E´, F´, and G´) correctly plotted. The student's explanation of the strategy used to draw the reflection "I counted the number of lines and blocks…" is not fully developed; there is no indication of how or which lines/blocks were counted. The representation and explanation demonstrate little ability to execute an appropriate strategy for a reflection. Further, the explanation of the relationship of the distances between line and points D and D´ is unclear ("are the same").

Score for Anchor Paper #2: Rubric Score 1

Annotation: This response demonstrates a minimal understanding and analysis of the problem. The representation of the reflection resembles the original shape to be reflected and has three points (C´, D´, and G´) correctly plotted. The student's explanation of the strategy used to draw the reflection "looked at were the dots were located…counted how many units were from the line…plotted my points and connected the dots" is almost complete. While this explanation provides some understanding of equidistance, no sense of perpendicular distance is conveyed. No explanation is given for the relationship of the distances between line and points D and D´.

Score for Anchor Paper #3: Rubric Score 2

Annotation: This response demonstrates a conceptual understanding and analysis of the problem. The representation of the reflection is correct, although the student has omitted the primes in the point labels. While the response lacks any written explanation of either the student's strategy for drawing the reflection or the relationship of the distances between line and points D and D´, a correctly drawn representation indicates the application of an appropriate strategy.

Score for Anchor Paper #4: Rubric Score 2

Annotation: This response demonstrates a conceptual understanding and analysis of the problem. The representation of the reflection is correct, even though points A´ and B´ are slightly off due to the use of a mira. "I…used a mirror to put the dots on the reflected line… trace the letters with the dots" provides an explanation of an appropriate strategy to reflect the shape. "On the reflected line" was understood to mean "over the reflected line," intimating the mira's appropriate placement. The explanation offered for the relationship of the distances between line and points D and D´ is incomplete and vaguely stated "…about 10 squares away" but does convey an understanding of equidistance. The student fails to address the perpendicular distance.

Score for Anchor Paper #5: Rubric Score 3

Annotation: This response demonstrates a complete understanding and analysis of the problem. The representation of the reflection is correct, but lacks point identification (a minor error). A complete explanation of an appropriate strategy is given. ("I followed the pattern…point G was ½ a space away from line , but in the other direction.") A complete understanding of the relationship of the perpendicular distances between line and points D and D´ also is provided. ("D is 5 points away from line , so D´ is 5 points away from line opposite the line.")

Score for Anchor Paper #6: Rubric Score 3

Annotation: This response demonstrates a complete understanding and analysis of the problem. The representation of the reflection is correct, including all point identification. A complete explanation of an appropriate strategy used to draw the reflection is given. ("…I counted the perpendicular distance from any point to line …I counted the same perpendicular distance only to the other side of line from line .") A complete explanation is provided for the relationship of the distances between line and points D and D´. ("Line is 5 units of diagonal squares from both of those points.")

Additional Scored Student Responses