Get students'
interest by asking, "Do you think the length of the cord and the size of the person matters when bungee jumping? Would it
be smart to lie about your height or weight?" Allow students to offer suggestions as to why an accurate estimate of height
and weight would be important to conduct a safe bungee jump.
**(Technology)**
You may also wish to show a short video about bungee
jumping. Some bungee videos are available on the following web sites (note that the third video shows the tribal ritual of
land diving, a precursor to bungee jumping, and may not be appropriate for all classrooms):
After a brief introduction, set up the lesson by telling
students that they will be creating a bungee jump for a Barbie^{®} doll. Their objective is to give Barbie the greatest
thrill while still ensuring that she is safe. This means that she should come as close as possible to the ground without hitting
the floor.
Explain that students will conduct an experiment, collect
data, and then use the data to predict the maximum number of rubber bands that should be used to give Barbie a safe jump from
a height of 400 cm. (At the end of the lesson, students should test their conjectures by dropping Barbie from this height.
If you school does not have a location that will allow such a drop, then you may wish to adjust the height for this prediction.)
Distribute the Barbie Bungee activity packet to each student. In addition, give each group of 3‑4 students
a Barbie doll, 15‑20 rubber bands, a large piece of paper, some tape, and a measuring tool. Be sure that all rubber
bands are the same size and thickness. Differences in rubber band elasticity will affect the results.
Before students begin, demonstrate how to create the
double‑loop that attaches to Barbie’s feet. Also show how a slip knot can be used to add additional rubber bands.
Then, allow students enough time to complete the experiment and record the results in the data table for Question 2.
After all groups have completed the table, ask them
to check their data. They should look for numerical irregularities. If any numbers in their table do not seem to fit, they
may need to re‑do the experiment for the number of rubber bands where the data appears abnormal. The teacher may need
to assist the students with measurements. (Common student errors include measuring incorrectly and adding too many or too
few rubber bands. As students conduct the experiment the first time, circulate and attempt to spot these errors as they occur.)
Note that the number of rubber bands in the first column increases by 2. This is so students consider the idea of slope
during the experiment. If the number of rubber bands increases by 1, then students are not required to think about what
the slope means. When increased by 2, however, students have to realize that the slope of the line actually represents
"centimeters per rubber band" instead of "centimeters per two rubber bands."
To create a graph of the data, you may wish to have
students use the Illuminations Line of Best
Fit activity, or allow them to enter the data in the Barbie Bungee
Spreadsheet (Excel).
At the end of the lesson, take students to a location
where Barbie can be dropped from a significant height. Possibilities include a balcony, the top row of bleachers, or even
standing on a ladder in an area with a high ceiling. Allow students to test their conjecture about the maximum number of centimeters
that can be used for a jump of 400 centimeters. |