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Session 4 - Interpreting Shape, Center and Spread

Interpreting Shape, Center, and Spread - Grade Band: High School).

Collaborative Activity #3 (10 - 15 minutes)

Activity: Height Activity & Answers 

Directions:

  1. Different types of spread: 
    1. There are 3 different types of spread that students need to know about, and then how they use them. 
    2. This is a helpful table to review (it is also at the bottom of page 4 of the Height Activity).

Focus: MP1: Make sense of problems and persevere in solving them and MP2: Reason abstractly and quantitatively

Name Range Interquartile Range Standard Deviation
How would you define this? The spread of all the data. The spread of the middle 50% of the data set. A measure of how much we might expect a member of a data set to differ from the mean.  
How do you find it? Subtract the minimum from the maximum 
(max-min)
Subtract Q1 from Q3
(Q3 - Q1)
Use a formula or a program that will calculate it for you.

What does it mean in the context of the Height Activity?

The student heights vary by 35 centimeters (from 155 - 190 cm). The middle 50% of the students vary in their height by 6 cm.

The standard deviation (found by using a calculator or other software) is 7.60.

This means the heights of the study vary, on average, by 7.6 cm from the mean height of 164.125 cm

Decorative question mark:

Why are students doing this/what are they getting out of it? 

Students will use four data sets and graph them. It is through this visual representation that students will understand that graphs can have different shapes. Because of these shapes, students need to use different measures of center (mean, median, mode) and different measures of spread (range, standard deviation, and interquartile range) to describe these graphs. 

Progress Activity

Directions:

  1. Students will use arithmetic to find the range and the IQR (Interquartile range). As a group, they should discuss the meaning. 
  2. The range describes the set of all possible answers (eg: Remember the snowfall activity?  The range of the snowfall is 63.6. This means that the snowfall varies from the highest snowfall to the lowest snowfall by 63.6 inches). 
  3. The IQR describes the middle 50% of the data set (eg: the middle 50% of the snowfall data shows that the snowfall varies by 46.7 inches)
  4. As students are working on the third part of the Height Activity, be sure that they can accurately find the range and the interquartile range. If students are unable to accurately find these measures, give them feedback or extra work until they can do so without assistance. If you like to keep track of what your students can accomplish, use Progress Monitoring Tool #3 to check if the students understand the concepts. 

Decorative question mark:

Why are students doing this/what are they getting out of it? 

From this students will learn the 3 different types of the spread of a data set. Though they will not calculate the standard deviation, knowing that standard deviation exists will be important to future statistical lessons.


Collaborative Activity #4 (40 minutes)

Activity: Test Data Activity & Answers

Focus: MP2: Reason abstractly and quantitatively and MP4: Model with mathematics

Directions:

  1. The first part of this activity is to practice finding the measures of the center (mean, median, mode) and the 5-point summary (min, max, q1, q3).
  2. The second part of this activity introduces the concept of the shape of the histogram, and choosing which measures of center and spread are best to be used with different shapes.
  3. Gather students in pairs or groups to work together through this activity. They can also complete it on their own if they choose to. 
  4. Make sure each student has a copy of the activity. They will not need any manipulatives but they will need a calculator and a writing utensil.

  1. Go through each problem on the lesson worksheet and follow the directions. 
  2. Students may need help in reading some of the language or figuring out the next steps.  
  3. Monitor and guide the learning as students complete the lesson.
  4. The activity should be reviewed at the end with these Test Data Activity & Answers

Progress Monitoring

Directions:

  1. In the Test Data Worksheet, check the answers to Part 1 before moving on to Part 2.  
  2. If the student does not have 80% accuracy (23 out of 28 correct answers) on Part 1, then you may want to go back and review before moving onto Part 2.

Decorative question mark:

Why are students doing this/what are they getting out of it? 

The students are practicing their algorithmic skills of solving for statistical values. It is important in this exercise that they are mathematically accurate.

Please Note

Decorative pencil icon

 If this activity seems to take a long time, this would be a good breaking point.