Introducing Graphing and Statistics in 7th Grade
Written, Edited, and Correlated by Michelle Burk, Ron Noble, and
William Hatchett

All materials, with the exception of a few worksheets, all
assessments, and rubrics, have been provided by the Shodor Foundation.
Abstract
The unit is designed to introduce middle school students to
statistical data and methods of representing data derived from the statistics.
It is a 20 hour module (5 hours instruction and 15 hours of lab work) which
allows the student to model life situations through the use of the graphs to
include circle graphs, histograms, bar graphs and stem and leaf graphs. The
primary lab tool being presented will be Project
Interactivate. As a result of this module, the student will have a firm
grasp of the subject and have improved understanding of statistics and how it
correlates to the world around them.
Objectives
Upon completion of this unit, students
will:
·
understand three
different measures of “center”
·
have been exposed to
multiple ways of expressing sets of numbers
·
have practiced their
arithmetic skills
·
have been introduced
to histograms and bar graphs
·
have understood the
difference between bar graphs and histograms
·
have seen examples of
how data can be represented in a variety of graphical forms
·
have been introduced
to the notion of stem-and-leaf plots have learned the terminology used with
stem-and-leaf plots
·
have used
stem-and-leaf plots to calculate mean, median, and mode of a set of data
·
communicate knowledge and understanding in everyday and
mathematical language
·
understand concepts and procedures from statistics
·
define and solve problems
·
use mathematical reasoning
·
formulate questions that can be addressed with data and
collect, organize, and display relevant data to answer them
·
select and use
appropriate statistical methods to analyze data
·
develop and evaluate inferences and predictions based
on data
Student Prerequisites
To complete this module, students should have a general
understanding of arithmetic operations including: addition, subtraction,
multiplication, and division of whole numbers and decimals (with or without
calculator use). Students will need the ability to use a mouse and browser.
Teacher Preparation
- Students
need access to a Java-capable browser and appropriate software
- Students
will need pencil, paper, and/or calculators
Unit Outline
- What
are statistics and data?
- Measures
of center.
- Graphing
(frequency table, histogram, bar graph, stem-and-leaf plot, pie chart)
References and Resources
Project Interactivate
Washington
State Essential Academic Learning Requirements
National
Council of Teacher of Mathematics Standards
Activities
- Measures
activity
- Sample
problems on mean, median, and mode
- Discussion
on mean, median, and mode
- Measures
exploration questions
- Histogram
exploration questions
- Sample
problems on histogram scales and impressions
- Class
interval discussion: scale and impression
- Plop
It activity
- Sample
problems on bar graph scales
- Vertical
scale discussion: increase or decrease
- Sample
problems on bar graph class intervals
- Histogram
vs. bar graphs discussion
- Sample
problems on comparing histograms and bar graphs
- Stem and
leaf plot discussion
- Worksheet
to accompany the stem and leaf plot lesson
- Circle
Graph (pie chart) exploration questions
- Pie chart
recording work sheet
- Activity Rubrics
Standards Addressed
Probability and Data Analysis
(National Council of Teachers of Mathematics)(NCTM)
Geometry (National Council of
Teachers of Mathematics)(NCTM)
Probability and Statistics
(Washington State Essential Academic Learning
Requirements)(EALR’s)
Number Sense (Washington State
Essential Academic Learning
Requirements)(EALR’s)
Geometric Sense (Washington State
Essential Academic Learning
Requirements)
(EALR’s)
Cross Curricular Connections
This module covers skills that are
used in all core academic and technology areas.
Assessment Techniques
Journal recording
Performance
assessment using paper and pencil
Student
assessment
Assigning
grades to journals
Glossary
Procedures For Mean, Median, Mode Lessons
- Instructor
will model the applet “Measures Activity” using
plant height data.
- Leading
Questions-----
- Q:
What do you think the mean is?
- Q:
Why do you think there is no mode?
- Q:
What do you think median means?
Assessment: In Journals----
- Students
will be asked to describe, in their own words, what statistics, data,
mean, median, and mode are as they pertain to data collection.
- Students
will be asked how mean, median, mode, and range relate to each other?
- Students
will be asked to described measures of center and their relationships to
statistics.
Procedures For Histograms and Bar Graph
Bar Graphs 
- Instructor
will model the applet “Plop It” by soliciting students’ birthday
month/date.
- Leading
Questions-----
- Q:
What can you say about what the graph is telling you?
- Q:
If you change the numbers on the vertical scale, what will that do to
the appearance of the graph?
- Students
will explore the mean, median, mode relationship to bar graphs through
“Plop It Exploration Questions”.
- In
groups of four, students will discuss and share with large group their
solutions to the exploration questions.
- Students
use graph paper and pencil to solve “Sample Problems on Bar Graph Scales”.
- In
groups of four, students will discuss and share with large group their
solutions to the sample problems and decide which vertical scale is most
appropriate for the given data sets.
- Determine,
by large group discussion, why a vertical scale is best for a particular
data set using “Vertical Scale Discussion: Increase or Decrease?”.
- In
journals, students define bar graph and communicate the purpose of
increasing or decreasing the vertical scale on a bar graph.
Assessment: In Journals----
- Students
will define bar graph and vertical scale.
- Students
will describe the purpose of increasing or decreasing the vertical scale
on a bar graph.
Paper
and pencil quiz.
A
web version is also available here.
Histograms 
- Instructor
will model the applet, “Histogram
Activity” using data sets in the activity.
- Leading
Questions-----
- Q:
Look at the word histogram. What do you think it means? (history)
(something written or drawn)
- Q: What
is happening to the picture of the graph as it is being changed (teacher
is changing class interval in the activity)?
§
Q: Is the data itself changing or is it the appearance
of the data changing?
- Students
will read “What?”, “How?”, and Why?” for the “Histogram Activity”, and
record the definitions of range, histogram, frequency, and class interval
in their journal notebook.
- Students
will explore given data as they solve the “Histogram Exploration
Questions” within the “Histogram Activity”.
- Instructor
and students will discuss the results of the “Histogram Exploration
Questions”.
- Class
discussion: “Class Interval Discussion: Scale and Impression”.
- Students
individually using paper and pencil solve “Sample Problems on Histogram
Scales and Impressions”.
- In
groups of four, students will discuss their answers to the sample
problems, deciding which interval is most appropriate for the given data
sets.
- Individual
groups will share their findings with large group.
- Determine,
by large group discussion, why a certain interval is best for a particular
data set.
- Students
describe class interval and its usage with histograms in their journal.
- Large
group discussion, “Histograms vs. Bar Graphs Discussion”.
- Assessment:
Using graph paper and pencil, individually, the students will complete,
“Sample Problems on Comparing Histograms and Bar Graphs”.
Paper
and pencil assessment.
A
web version is also available here.
Assessment: In Journals----
- Students
will define class interval, range, histogram, frequency, and class
interval.
- Students
will describe class interval usage and its relationship with histograms
Lesson on Stem and Leaf Plots 
- Students
need to read the “What?” page in the “ Stem-and-Leaf
Plotter Activity”.
- In
small groups students discuss the definition and usage of stem-and-leaf
plots.
- In
large group students will share small group results.
- Instructor
and students will debrief using the “Stem-and-Leaf Plots Discussion”.
- Instructor
models how to use the “Stem-and-Leaf Plotter Activity”.
- Students
will complete problems 1 and 2 using the “Stem-and-Leaf Plotter Activity”.
- Review
results of problems 1 and 2 with the students.
- Using
graph paper and pencil, students construct stem-and-leaf plots for
problems 3 and 4.
Paper
and pencil assessment.
A
web version is also available here.
Assessment: In Journals----
- Students
will record the definition and purpose of stem-and-leaf graphs and their
relationship to mean, median, and mode of a data set.
- Students
will describe the relationship between stem-and-leaf graphs and measures
of center.
Lesson on Pie
Charts 
- Instructor
models the applet, “Pie
Chart Activity:” using data generated by asking students which of these
5 candy bars they prefer: Snickers, Kit Kat, Butterfinger, Big Hunk, Baby
Ruth. Data will be converted from numbers to percentages to degrees.
- Students
record activities on the >““Pie Chart Recording Worksheet” for a 24-hour period
following the modeling lesson.
- Students
complete the pie chart data sheet and use “Pie Chart” applet to compare
results.
- Students
will explain any variations from their graph to the applet comparison
graph in their journals.
Assessment: In Journals----
- Students
will record any variations from their graph to the applet comparison
graph.
The activity rubric will also be used to assess the final assessment.