Misleading Graphs
Misleading Graphs Lesson Plan
Abstract
This lesson will challenge students to think creatively by having them design
and build water balloon catchers from random scrap materials, while requiring them to
take into consideration a multitude of variables including: cost, maintenance, total
capacity, etc. After completing their water
balloon catchers, students will collect data based on the performance of all catchers
designed by the class. Students will then construct at least two bar graphs to be
used in a commercial advocating the purchase of their group's catcher.
Standards (NCTM Grades: 3-5)
Algebra
Use mathematical models to represent and understand quantitative relationships
- model problem situations with objects and use representations such as
graphs, tables, and equations to draw conclusions.
Data Analysis and Probability
Formulate questions that can be addressed with data and collect, organize,
and display relevant data to answer them
- Design investigations to address a question and consider how data-collection
methods affect the nature of the data set
- Collect data using observations, surveys, and experiments
- Represent data using tables and graphs such as line plots, bar graphs, and
line graphs
Select and use appropriate statistical methods to analyze data
- Describe the shape and important features of a set of data and compare
related data sets, with an emphasis on how the data are distributed
- Use measures of center, focusing on the median, and understand what
each does and does not indicate about the data set
- Compare different representations of the same data and evaluate how well each
representation shows important aspects of the data.
Understand and apply basic concepts of probability
- Describe events as likely or unlikely and discuss the degree of likelihood
using such words as certain, equally likely, and impossible
- Predict the probability of outcomes of simple experiments and test the
predictions
Student Prerequisites
- Technological:
Students must be able to:
- perform basic mouse manipulations such as point,
click and drag
- use a browser such as Netscape for experimenting with
the activities
Teacher Preparation
Have a pretend store set up where students can "purchase" scrap materials.
Students will need:
- access to a browser.
- enough scrap materials so that each group is able to design and construct water
balloon catchers.
Lesson Outline
- Focus and Review
- Review vocabulary covered to this point.
- Review all types of graphs you have covered to this point.
- Explain the term misleading graph.
- Begin a
discussion
on how misleading graphs are used in advertising.
- Objectives
Students will analyze and compare graphs in order to identify appropriate
conclusions and determine if a particular graphical display is misleading.
- Teacher Input
- Guided Practice
- Allow time for the students to familiarize themselves with the applets while
you circulate throughout the room answering any questions.
Teacher Input
- Have students turn off their monitor.
- Explain to the students their assignment:
You are to work in pairs to construct a water balloon catcher. You have been
alloted X amount of dollars to purchase supplies. (Have a store set up in
the rear of the room. Materials can consist of almost any type of scrap you can
collect from around the school, your home, or that your students collect and
donate.) After these water balloon catchers are complete we will test them as a
class. Each group will have the opportunity to drop 10 water balloons into their
catcher in order to collect data on their group's catcher and their competitor's
catchers based on:
- How many water balloons landed in the catcher?
- How many water balloons completely missed the catcher?
- How many water balloons dropped into the catcher and bounced out?
- Total number of balloons the catcher will hold at any given time.
- Did the catcher require any maintenance?
- Number of broken balloons.
- Number of balloons caught without breaking.
- Cost of balloon catcher.
- Total cost of balloon catcher including maintenance fees.
Once all the data has been collected you will design a commercial enticing people to
purchase your water balloon catcher over your competitor's. You will need to
include at least two graphs in your commercial. (These graphs can be misleading but
are not required to be.)
- Independent Practice
- Have the students construct their water balloon catchers.
Guided Practice
- Test the catchers and collect the data on the data sheet as a class.
Independent Practice
- Have the students design their graphs using the
Bar Graph and/or the
Histogram applets.
- Have students design their commercials.
- Have each group preform their commercial in front of the class.
- Have all the competing groups vote on which water balloon catcher they would
buy based on the commercials (excluding their own).
- Closure
- Select a few of the commercials to discuss.
- Discuss the graphs contained in the chosen commercials and why they may or
may not be misleading.