Getting Started 
Misconception/Error The student does not address the association or describes it incorrectly. 
Examples of Student Work at this Level The student:
 Says there is no association or describes it as negative or nonlinear.
 Describes the association only as weak and incorrectly interprets the slope of a line of fit.

Questions Eliciting Thinking What are the two variables graphed on this scatterplot?
What are the coordinates of this point (indicate a particular point on the graph)? Can you interpret this point in the context of the data?
What is happening to the time spent watching advertisements as you look from left to right on the horizontal axis? What is happening to percent willing to buy crackers as you look from left to right on the horizontal axis?
What about this pattern caused you to describe it as nonlinear? What kind of curve would better model this data than a line? 
Instructional Implications Review terms used to describe functional relationships: constant, linear, nonlinear, exponential, increasing, decreasing, positive, and negative. Emphasize the distinction between linear and nonlinear patterns in scatterplots. Point out that a linear association can be approximated by a straight line fitted to the data points. Remind the student that a positive linear association can be described by a line with a positive slope, and a negative linear association can be described by a line with a negative slope. Assist the student in recognizing that the association between the variables in the scatterplot can be described as a weak positive linear relationship. Guide the student to interpret the relationship in the context of the data (i.e., as time spent watching advertisements increases, willingness to purchase crackers tends to increase).
Provide additional scatterplots that display various types of associations and model describing the relationship between the variables. Address any clustering or evidence of outliers and explain these features in terms of the context of the data. Provide additional opportunities for the student to construct and interpret scatterplots by describing associations and identifying clusters and outliers. 
Making Progress 
Misconception/Error The student provides an incomplete description of the association. 
Examples of Student Work at this Level The student:
 Describes the association as weak, positive, and/or linear without regard to the context of the data.
 Describes the changes in each variable without making their association explicit.
 Describes the association in context but does not address the strength of the relationship.

Questions Eliciting Thinking What are the two variables graphed on this scatterplot? Can you describe the association in the context of these variables?
Would you describe this association as linear or nonlinear? Positive or negative? How would you describe the strength of this association?
How would you complete this sentence, “As time spent watching advertisements increases, the…”? 
Instructional Implications Review terms used to describe functional relationships: constant, linear, nonlinear, exponential, increasing, decreasing, positive, and negative. Model describing the association between the variables in the scatterplot as a weak positive linear relationship. Guide the student to interpret the relationship in the context of the data (i.e., as time spent watching advertisements increases, willingness to purchase crackers tends to increase). Provide additional scatterplots that display various types of associations and ask the student to describe the relationship between the variables.
Provide opportunities for the student to fit lines to linearly related data. Introduce the use of technology to construct scatterplots and generate lines of best fit. Remind the student that a line is a good fit for a set of data if the distances between the data points and the line are small. Explain that data points in strong associations show little deviation from a line used to model the association. Weak linear associations will still follow a linear pattern, but data points are more scattered around the line that models the relationship. Show the student several scatterplots (e.g., ones with a strong positive linear, strong negative linear, weak positive linear, weak negative linear, and no linear relationship) and model a line of good fit for each example. Explain that there are mathematical techniques for locating the line so that the distance between the data points and the line is minimized.
Provide the student with two small scatterplots (6 – 8 data points) with lines of best fit drawn: one that displays a strong linear relationship and one that displays a weak linear relationship. Ask the student to draw a vertical line segment from each data point to the line of fit. Then have the student measure the line segments and sum their lengths. Explain that the line segments represent each data point’s distance from the line of fit. Therefore, a smaller sum indicates a better fit. 
Got It 
Misconception/Error The student provides complete and correct responses to all components of the task. 
Examples of Student Work at this Level The student explains that as time spent watching advertisements increases, willingness to purchase crackers increases. Additionally, the student states that the association is linear, and positive but weak (or does so upon questioning).

Questions Eliciting Thinking Would you describe this association as linear or nonlinear? Positive or negative? How would you describe the strength of this association (if the student did not already address these qualities in his or her response)?
Do you think one of these variables is a cause and the other is an effect? Can you explain?
Do you see any evidence of outliers?
What feature of the scatterplot indicates the strength of the association? 
Instructional Implications Review the relationship between correlation and causation (i.e., a correlation does not imply causation). Group the student with other Got It students to brainstorm possible reasons for a given association (e.g., a change in Variable A may cause a change in Variable B, or the reverse may be true, or both may be affected by a third factor).
Provide the student with a sample data set. Ask the student to construct a scatterplot, draw a line of good fit, and approximate the equation of the line. Then ask the student to use the equation to make predictions about specific values of one or both variables.
Consider implementing other MFAS tasks for standard (8.SP.1.1). 