Wyoming Math 8.SP.4

8.SP.4 is a cluster heading. These are the individual standards under it.

• 8.SP.4a

  Construct and interpret a two-way table summarizing data on two categorical variables collected from the same subjects.

• 8.SP.4b

  Use relative frequencies calculated for rows or columns to describe possible association between the two variables.

01

What Students Need to Do

Record two answers from each person in a two-way table. Calculate percentages within rows or columns, then compare groups to look for a possible association.

02

What Mastery Looks Like

A student puts each person's paired answers in one cell and totals the rows and columns. They use the right group total to find each percentage and describe the difference without claiming one answer caused the other.

03

Common Misconceptions

Students may compare raw counts even when the groups are different sizes. They may divide by the total number of people instead of a row or column total, or mistake an association for proof of cause.

04

How to Assess It

Exit ticket: Of 20 bus riders, 12 packed lunch. Of 10 nonriders, 3 packed lunch. Build a two-way table, find the packed-lunch percentage for each group, and describe any association.

1. 01

   Ask classmates whether they rode the bus and packed lunch today; place each person's paired answers in one cell of a four-cell table.

2. 02

   Ask: If 60% of bus riders and 30% of nonriders packed lunch, what association do you see, and what can't you conclude?

3. 03

   Pairs race to sort 16 bus-and-lunch cards into a two-way table, then compare packed-lunch percentages for bus riders and nonriders.

4. 04

   Give students a mock cafeteria roster marked by grade and packed lunch yes/no; compare rates by grade to plan lunch orders.

• 6.SP.5c

  Find quantitative measures of center (median, mode and mean) and variability (range and interquartile range). Describe any overall pattern (including outliers, ...

• 7.SP.4

  Given measures of center and variability (mean, median and/or mode; range, interquartile range, and/or standard deviation), for numerical data from random sampl...