The student will complete product analyses by calculating
the mean, median, mode, and range for a given set of item
The student will complete sales analyses by calculating
mean, median, and range using daily sales data.
The student will understand how statistics are used to
collect, organize, and interpret data.
Connection to Bloom’s Taxonomy
- Crayons or Colored Pencils
- Index Cards
- Worksheets for lesson plan 6 (see sidebar)
Ask students to define the word statistics. As a class,
brainstorm possible definitions. Then provide students with
dictionaries or access to on-line dictionaries to develop one
definition that describes the term accurately. In general,
statistics is a mathematical or scientific term to describe the
collecting, organizing, and interpreting of data. Statistics may
include creating graphs, calculating averages, or determining
We live in a world filled with statistics, yet we are often
unaware of their usefulness in our daily lives. Have students
think about statistics by asking them to identify and list when
averages are used. Provide newspapers as one possible way to
jump start the activity.
Some possible responses may include the following:
- The average price of a gallon of gasoline
- Baseball batting averages
- Bowling averages
- Average temperature
- Average rainfall or snowfall
- Average hospital stay for patients
- Average income or age, collected as census data
Average wait time (on the telephone) when on-hold for customer
- Product price averages for dairy products
- Average grade on a test
- The Down Jones Industrial Average (stocks)
Average weight or height for a child of a certain age (used by
Exploring and Learning
Four common statistical terms used to analyze data are
mean, median, mode, and
range. Review the following definitions and how to
The mean is the average. It is calculated by
adding values (data) and dividing by the number of values
The median is the middle value in a series of
values placed in numerical order. For odd sample sizes,
simple use the middle value. For even sample sizes, take
an average of the two middle values.
The mode is the most common value in a series of
values. If no value occurs more than once, then there is
no mode. If two values occur more than once and the same
number of times, the sample is called bimodal.
The range is the difference between the largest
and smallest values in a sample.
Pair students together and provide each pair with a copy of
Weather Data Worksheet (PDF).Student will analyze a sample 5-day weather forecast to
calculate the following statistics:
- Average (Mean) High Temperature
- Average (Mean) Low Temperature
- Median High Temperature
- Median Low Temperature
- Mode High Temperature
- Mode Low Temperature
- Range for High Temperatures
- Range for Low Temperatures
Together as a class, review the calculations for each weather
temperature statistic. It maybe helpful to guide students
through each of the calculations in order to reinforce the
concept of how to calculate the mean, median, mode and range.
Refer to the
Weather Data Worksheet Key (PDF)
Based on the calculated weather temperature statistics,
discuss the following questions:
Was the Average (Mean) High Temperature above 85 degrees?
Was the Average (Mean) Low Temperature below 60 degrees?
What two values were exactly the same?
(The Median High Temperature and the Mode High
Which had a larger range over a 5-day period, high
temperatures or low temperatures?
(High temperatures ranged 21 degrees versus low
temperatures that ranged 18 degrees)
Present students with the following scenario:
RG and Hannie are working at the Raymond Geddes Elementary
School Store. Sniffer has asked them to analyze their top
20 school store items. He would like to know the average
(mean) retail price of those items, the median retail
price, the mode, and the range. In addition, Sniffer would
like RG and Hannie to analyze a week’s worth of sales by
calculating several statistics: average daily total sales
amount, the median daily total sales amount, and the range
for daily total sales amounts for the week.
Can you help RG and Hannie calculate and analyze the
Challenge: If you run your own school store, or ran the
school in a previous Geddes lesson plan, update the sales
spreadsheet with your own sales data.
To help complete the scenario, pair students together and
provide each group with the following:
Explain and list on the board, or as a transparency, the
following instructions to complete the scenario:
Place the items in the
Geddes Kit List (PDF)
in order by retail price from lowest to highest. If
students are familiar with using spreadsheet software,
encourage them to input the list into a spreadsheet to
complete the product analysis.
Record answers on the
Product Analysis Worksheet (PDF)
Next, use the
Weekly Sales Results Excel Spreadsheet
to analyze sales results for one week.
Place the daily total sales amounts in order from
lowest to highest.
Calculate the average daily total sales amount for
- Calculate the median daily total sales amount.
Calculate the range for the daily total sales amounts.
Record answers on the
Sales Analysis Worksheet (PDF).
As a class, review the results. Refer to the
Product Analysis Worksheet Answer Key (PDF)
Sales Analysis Worksheet Answer Key (PDF)
Discuss the following sales analysis questions:
Which day of the week generated the most sales?
Which day of the week generated the least sales?
What was the range between the highest sales day and the
lowest sales day? ($14.76)
Brainstorm some possible reasons to explain why sales on
Friday were so much better than sales on Monday for this week.
Some possible explanations include the following:
Students may not remember to bring in their money when
returning back to school after the weekend.
The school may be able to send out more reminders during
the week advertising the
school store and its products.
Teachers may have completed their lessons with students
providing students more time at the end of the week to
shop at the school store.
Students purchased more of the most expensive item
(6-Color Pens) on Friday. This may have helped to boost
sales for the day.
There may not be any particular reason since we have only
one week’s worth of sales. Students would need multiple
weeks of sales results to determine if Friday always
remained the best day of the week.
Review the definition of statistics—collecting, organizing,
and interpreting data. Do students feel they were successful
using statistics to analyze product and sales data?
Lead a short discussion on some of the shortcomings of
statistics. Statistics can be helpful to analyze data.
However, statistics may also be misleading. As shown above,
students cannot pinpoint the exact reasons why Friday
generated the highest sales for the week. Statistics do not
take into account the human factor - why people make the
decisions they do. Averages, in particular, can be misleading.
They may be affected by outliers, extreme high and low values.
Often times, mathematicians will drop the highest and lowest
values in a sample in order to arrive at a more representative
Extended Learning and Practice
Spend more time analyzing the
Weekly Sales Results Excel Spreadsheet.
What was the average daily number of items sold for the
( 656 ÷ 5 = 131 items )
What was the median number of daily items sold?
( 134 items )
What was the range?
( 148 - 105 = 43 items )
PBS Kids ZOOM website
at for another in-class activity to calculate averages. How
heavy are your students’ backpacks? Collect, organize, and
calculate data just like ZOOM did.
The lesson objectives can be assessed by evaluating the
Weather Data Worksheet (PDF), the
Product Analysis Worksheet (PDF), and the
Sales Analysis Worksheet (PDF)
Weather Data Worksheet Answer Key (PDF), the
Product Analysis Worksheet Answer Key (PDF), and the
Sales Analysis Worksheet Answer Key (PDF).
Assessment of Student Progress PDF
to assess students’ overall abilities to meet the lesson’s
learning objectives, which include analyzing product price and
sales data by calculating mean, median, mode, and range; and
understanding how statistics are used to collect, organize, and
Provide each student with an index card and have them answer the
following questions on one side of the card:
What are two new things that you have learned?
What else would you like to learn about this topic?
On the back side of the index card, instruct the students to
draw a picture of something they learned about during this
lesson. The index cards can be hole punched and held together
with a simple shower curtain ring.