Education Technology
Grade Level 6
Activity 8 of 24
In this lesson, students develop a working definition of outliers and use it to analyze data sets.

Planning and Resources

Students learn to identify outliers in a set of data through both visual and computational approaches. They can describe the impact of outliers on measures of center and spread.

upper quartile
lower quartile
interquartile range

Standard: Search Standards Alignment


Lesson Snapshot


Outliers are values that lie outside 1.5 IQR values from the upper or lower quartile in a box plot.

What to look for

Students should recognize that outliers have no impact on the median and interquartile range.

Sample Assessment

To find an outlier you need to know?

I. The median
II. The minimum and maximum
III. The quartiles

a. All of the above
b. I and III
c. II and III
d. I and II

Answer:  C

The Big Idea

Outliers are extreme data values, worth noting for contextual reasons and for their effects on center and spread.

What are the students doing?

Students identify outliers visually and using the formula; noticing the impact of outliers on the mean and mean absolute deviation.

What is the teacher doing?

Encourage students to think of plausible explanations for outliers in the context of the data.