aidemia--modules-lessonanyideas_request	Give a creative idea how to organize and what to do at a part of the lesson
What part of a lesson	Introduction
Which subject	Mathematics
What age group	Year or Grade 9
What topic	Outlier and how they affect the mean and median
Quantity	1
Any other preferences	lilly0523@gmail.com

Introduction to Outliers in Mathematics

Welcome to today's mathematics lesson! In this part of our lesson, we will dive into an exciting concept: outliers, and how they influence measures of central tendency, such as mean and median. To kick things off, we'll engage in an interactive activity that will help solidify your understanding of these concepts.

Objectives

By the end of this introduction, you should be able to:

• Define outliers and identify them in a data set.
• Understand how outliers affect the mean and median of a data set.
• Use real-world examples to appreciate the impact of outliers.

Interactive Activity: "Data Detective"

Overview

In this activity, you will become a "Data Detective," working in pairs to analyze a provided data set. Your mission is to identify outliers and calculate the mean and median, noting how the presence of any outliers impacts these measures.

Materials Needed

• Printed copies of a data set (see below)
• Calculators
• Chart paper and markers (for group presentations)
• Sticky notes for team reflection

Data Set

Score
82
88
91
76
85
200
79
87
84
90

Instructions

1. Pair Up: Form pairs with a partner. Each person will take turns as the "analyzer" and the "reporter."

2. Identify Outliers: Using the data set provided, discuss as a pair which values you believe are outliers. An outlier is typically a value that is significantly higher or lower than the others.

3. Calculate the Mean and Median:

   • Mean: Add all the scores together and divide by the number of scores.
   • Median: Organize the scores in order and find the middle value (or average of the two middle values if there is an even number of scores).

4. Evaluate Impact:

   • First, calculate the mean and median without the outlier.
   • Then, remove the identified outlier and re-calculate the mean and median of the new data set.

5. Reflection: Write down your thoughts on how the mean and median changed and discuss why you think outliers have such a significant effect on statistical measures.

6. Group Discussion: Share your findings with the class. What outlier did you find, and how did it affect your calculations? Use the chart paper to present your conclusions visually!

Conclusion

Outliers can dramatically alter the mean and median, skewing data interpretations. By understanding this concept, you will be better equipped to analyze real-world data effectively.

---

Wrap-Up Questions

• What is an outlier?
• How did the outlier affect the mean of your data set?
• Why might it be important to recognize outliers in research and statistics?

We hope this introduction has sparked your interest in outliers and prepared you for further exploration in our mathematics journey. Let’s get started with our "Data Detective" activity!