8.SP.1: Scatter Plots and Association
Also written as 8.SP.A.1 and CCSS.MATH.CONTENT.8.SP.A.1 · Cluster: Investigate patterns of association in bivariate data.
The Official Wording
Construct and interpret scatter plots for bivariate measurement data to investigate patterns of association between two quantities. Describe patterns such as clustering, outliers, positive or negative association, linear association, and nonlinear association.
Common Core State Standards, Grade 8, Statistics & Probability · Read it at the source · Checked October 14, 2026
What 8.SP.1 Means in Plain English
Eighth graders plot paired measurements, like each student’s weekly typing practice and typing speed, then describe the cloud: rising or falling (positive or negative association), straight or curved (linear or nonlinear), any clusters, and outliers such as the one-hour student who types 70 words a minute.
Describing comes before modeling: 8.SP.2 draws a line through a linear cloud and 8.SP.3 uses its equation. In high school the same plots get a correlation coefficient and the warning that association is not causation (HSS-ID.9).
8.SP.1 I Can Statements
- I can make a scatter plot from paired data.
- I can describe an association as positive, negative or none.
- I can point out clusters, outliers and curved patterns in a scatter plot.
8.SP.1 Worked Example
Ten students’ practice hours and typing speeds, plotted and then described the way the standard lists it.
Ten students recorded their weekly typing practice in hours and their typing speed in words per minute: (1, 22), (2, 25), (2, 28), (3, 30), (4, 34), (5, 37), (6, 41), (6, 44), (7, 46), (1, 70). Make a scatter plot and describe it.
- Choose the axes. The quantity that might explain the other goes across, and both axes count in equal steps.x: hours, 0 to 8 by 1s; y: words per minute, 0 to 80 by 10s
- Plot each student as one point, and do not connect them.10 points, from (1, 22) up to (7, 46), plus (1, 70)
- Describe the direction: as practice goes up, speed tends to go up.Positive association
- Describe the form: the points climb at a steady rate, close to a straight path.Linear, about 4 more words per minute per extra hour
- Name anything that does not fit the pattern, in context.Outlier: (1, 70), one hour of practice but the fastest typist
Check it: Cover the outlier and look again: the other nine points rise from 22 to 46 as hours go from 1 to 7, an increase of 24 over 6 hours, about 4 per hour.
Common Mistakes with 8.SP.1
Connecting the dots
A line drawn from point to point, left to right, like a line graph
Try this: Leave the points unconnected: each is a separate student, and the pattern is in the whole cloud, not a path.
Letting an outlier set the direction
“No association, because the fastest typist practiced least.”
Try this: Describe the main pattern first, then name the outlier separately; one point at (1, 70) does not erase nine rising points.
Numbering only the data values on an axis
A y-axis labeled 22, 30, 46, 70, the values that appear in the data
Try this: Number each axis in equal steps, like 0 to 80 by tens, before plotting, so distances on the page mean equal amounts.
Where 8.SP.1 Fits
Practice 8.SP.1
Quick Check
- As the outside temperature rises, sales at a hot chocolate stand fall. What kind of association is that?
- A plot of minutes since a cup of cocoa was poured against its temperature falls steeply at first, then levels off. Is the association linear?
- Nine points rise steadily from (1, 10) to (9, 50), and one sits at (8, 5). How would you describe the plot?