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The task
The teacher gave the following instructions:

Collect everyone’s height measurement in inches.
Make a line plot with the data.
Write about what you noticed about the data.

Circumstances of performance
This sample of student work was produced under the following conditions:

- alone - in a group
- in class as homework
- with teacher feedback with peer feedback
timed - opportunity for revision
This work sample illustrates a standard-setting
performance for the following parts of the standards:
a Statistics and Probability Concepts: Collect and organize data to answer a question.
b Statistics and Probability Concepts: Display data.
c Statistics and Probability Concepts: Make statements and draw simple conclusions based on data.
a Mathematical Communication: Use appropriate mathematical terms, vocabulary, and language.

What the work shows
a Statistics and Probability Concepts: The student collects and organizes data to answer a question….
The student began with the question of how tall her classmates were, and collected and organized data to answer this question.

b Statistics and Probability Concepts: The student displays data in line plots….

c Statistics and Probability Concepts: The student makes statements and draws simple conclusions based on data; that is, the student:
• reads data in line plots….

• compares data in order to make true statements, e.g., “seven plants grew at least 5 cm.”

The student made true statements about the range, “bumps,” “holes,” outlier, and median.

• identifies and uses the mode necessary for making true statements, e.g., “more people chose red.”

• makes true statements based on a simple concept of average (median and mean), for a small sample size and where the situation is made evident with concrete materials or clear representations.
Note: The median is incorrect because the student omitted one height measurement.

The revision provides further evidence of the student’s understanding.

a Mathematical Communication: The student uses appropriate mathematical terms, vocabulary, and language, based on prior conceptual work.
Appropriate use of mathematical terms and vocabulary is evident in these parts of the work particularly, and is supported by evidence throughout the work.

The line plot is incorrect since the values should be placed at equal intervals.
The student gave the correct median for the students in the class. However, the student incorrectly stated that the median is 57 . The correct median is 57 . Since the last value of the line plot is below the rest of the line plot, the student may have forgotten the last value (the teacher’s height) when computing the median.