8th Grade Scatter Plot Correlation Quizzes

This topic is a cornerstone of the Grade 8 Common Core State Standards for Statistics & Probability (8.SP). At this level, students are expected to construct and interpret scatter plots for bivariate data to investigate patterns of association. Key skills include identifying linear and non-linear associations, recognizing outliers, and modeling linear relationships with a trend line.

Use a memorable, slightly absurd example. For instance, show data with a strong positive correlation between ice cream sales and the number of drownings. Ask students if eating ice cream causes drowning. This leads to a discussion about a third, "lurking" variable (in this case, warm weather) that influences both.

A primary challenge is internalizing the distinction between correlation and causation. Students may also struggle to describe the form of an association (linear vs. non-linear) or identify the influence of outliers on the overall trend. They might also overstate the precision of predictions made from an informal trend line.

The practice problems require students to analyze bivariate data from real-world contexts. They will construct plots, describe patterns of association (positive, negative, linear, non-linear), identify outliers, and informally fit a straight line to model the data.

Use this quiz as a formative assessment. Assign it as a digital quiz on Wayground to get instant data on student performance, or print the PDF for a paper-and-pencil quiz. The included answer key allows for efficient grading and review of student work.

For students who need reading support, use Wayground's Read Aloud feature on the digital version of the quiz. For those who find visual information overwhelming, you can create a modified printable version with fewer data points per graph or use the platform's tools to increase font size and spacing for better readability.