73Egg Bungee

Science Scoop In this activity, the kids are given a problem to solve: design a bungee

jump for an egg. As the kids try to solve the problem, they follow the

five steps of technological design:

• Identify the problem

• Design a solution

• Implement the solution

• Evaluate the solution

• Share results

Technological design offers kids a chance to apply science to real-

world problems. So, what’s the science behind designing an egg bungee

jump? When you launch the egg, it falls toward the ground because

of gravity. As the egg falls, its weight stretches the nylon stocking. The

stocking stretches because it is elastic. A material is described as elas-

tic if it has the ability to return almost to its original shape after it has

been stretched or squashed by a force. Due to its elasticity, the stock-

ing slows down the egg until it stops falling. Then, the stocking springs

back toward its original shape, pulling the egg up and away from the

ground. The amount the stocking stretches depends on the weight of

the egg and how fast the egg is falling.

Egg Bungee JumpOverview

ScienceConcept

Try It Out ZOOMon: Change One Variable

Share Results

Technological Design

Invent a bun-gee jump for an egg using nylon stockings.

• Length of nylon stocking

• Weight of egg

• Type of stocking

• What design did you use?

• How successful was your design?

• How might you change your design

if you tried the activity again?

Club TM

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74Egg Bungee

Find Out More How Science Works: 100 Ways Parents and Kids Can Share the Secrets of Science Hann, Judith. Pleasantville, NY: Reader’s Digest, 1991.

Read the “Stretching and Squashing” section in the Energy, Forces, and Motion chapter to find out more about elasticity.

Usborne Essential Guides: Essential ScienceWingate, Philippa, Clive Giford, and Rebecca Treays. London, England: Usborne Publishing 1992.

Check out this book for background information on elasticity, weight, and gravity.

Elasticityschool.discovery.com/

homeworkhelp/worldbook/

atozscience/e/175580.html

This site offers a brief explanation of elasticity.

World’s Highest Bungy JumpAfrican-edventure.org/ed/

bungypage/fullbungy.html

A physicist describes the science behind bungee jumping from the perspective of a bungee jumper.

By changing the length of the nylon stocking, you can adjust how

close an egg comes to the floor. You can increase the length by tying

stockings to each other or decrease the length by cutting or knotting

the stockings.

The weight of the egg is what stretches the stocking. Each egg has

a different weight and stretches the stocking to a different length. It’s

important to have the “test” egg weigh roughly the same as the real

egg. Otherwise the final launch may miss its mark.

Different types of stockings have different degrees of elasticity. As

you stretch a stocking again and again, it will lose some of its elasticity

because the fibers become “fatigued” and do not return to their

original length. (Think of how the stretchiness of a new rubber band

compares to that of an old rubber band.)

Set Up • Watch the Egg Bungee Jump video segment, and try the activity

yourself before the meeting.

• Post the new ClubZOOM Board activities (see end of section).

• Set up a VCR and monitor to show the Egg Bungee Jump video

segment (optional).

• Collect materials for the ClubZOOM Box. For each kid, make cop-

ies of the Egg Bungee Jump activity handout and the Stay Tuned (see

end of section).

To Share

• masking tape• scissors• newspaper• ZOOM Challenge (see end of section)

For Demonstration

• yardstick or measuring tape • nylon stockings

Have extra materials available so the kids can test different variables.

Materials

For Each Pair

• egg• nylon stocking• plastic sandwich bag• 25–30 pennies • ruler• 2 paper cups• Egg Bungee Jump handout (see end of section)• Stay Tuned (see end of section)

Club TM

75Egg Bungee

Run the Meeting

Kick Off the Meeting (5 minutes) Welcome the kids and ask for a volunteer to decipher the

Stay Tuned. (Answer: Drop an egg without breaking it.)

Then have another volunteer read the ZOOM Challenge.

Try It Out (15 minutes) ◆ Demonstrate the elasticity, or stretchiness, of nylon stockings.

Measure one stocking leg. Then ask a volunteer to hold one end

of the leg, while another volunteer pulls from the other end. Have

a third volunteer measure how long the stocking is now. Subtract

to find out how much the stocking stretched. Explain that the

weight of the egg provides a force, similar to the volunteer pulling

on the stocking, that stretches the nylon. The kids will need to

consider the stretchiness of a stocking and the weight of an egg as

they build their bungee designs.

◆ Explain how you will launch each egg and measure where it stops.

(To launch the eggs, stand on a chair and raise your arm to the

same starting height for each release. To measure how close an

egg comes to two inches above the floor, put a piece of masking

tape between two chair rungs at that height. When you drop an

egg, have a volunteer watch the tape at eye level to observe where

the egg stops.)

◆ Organize the kids into pairs and distribute the activity materials.

As the kids design their bungee jumps, remind them to think about

the stretchiness of the nylon stocking, the weight of the egg, and

the height of the launch point. Then have them test their bungee

designs with “test eggs” that weigh roughly the same as real eggs.

(See Activity Tips for how to make test eggs.)

1

2

Activity Tips • To make test eggs that

weigh about the same as real eggs, kids can use a simple scale balance. To make a scale balance, tape a paper cup to each end of a ruler. Put the ruler on top of a small object (such as a paper clip box or a small pad of Post-It™ notes) and center it so that the two ends balance. Put an egg in one cup. Predict how many pennies are needed to bal-ance the ruler. Then add pennies to the other cup until the ruler is balanced.

• To save time or when work-ing with younger kids, make test eggs ahead of time. For each test egg, put twenty-five pennies (equal to the weight of an average egg) in a small plastic bag. Secure each bag by tying a knot.

Club TM

76Egg Bungee

Share Results (10 minutes)

Have the kids share their bungee jump designs and draw conclusions

about how they worked.

• What design did you use?

• How successful was your design?

• How might you change your design if you tried the activity

again?

Have the kids write or draw their results on the back of their activity

handouts. If they have difficulty, use the questions above to guide them.

Then have the kids post their results on the ClubZOOM Board.

Don’t Forget Square or Rectangle!

Remind the kids to keep collecting data to add to the Data Chart. Have they measured other members of their afterschool program yet?

ZOOM LinksVisit the ZOOM Web site and continue exploring technological design:

Bungee Jumppbskids.org/zoom/sci/

bungeejump.html

Visit the online version of Egg Bungee Jump to see the results posted by other kids.

Financial Supportpbskids.org/zoom/sci/

financialsupp.html

Try to make a tower as high as you can using 50 straws and clay.

Crazy Straw Bridgepbskids.org/zoom/sci/

strawbridge.html

Build a bridge that spans thirty centimeters and supports the most weight it can, using only straws and paper clips.

4

5

Send It to ZOOM!Remind the kids to send their results and ideas about egg

bungee jump design to ZOOM. They can do this by mailing

their activity handouts to ZOOM or by visiting the ZOOM

Web site at pbskids.org/zoom/sendit/sci-exp.html

Wrap Up (5 minutes)

Hand out the activity stickers and the Stay Tuned coded message

for the next meeting.

ZOOMon (15 minutes)

How close did the test egg come to two inches from the floor? Once

the kids have tried their bungee jumps with test eggs, ask them to

evaluate their designs so far. What might they need to change before

they use real eggs? What happens if they change the cord length by

adding stockings or cutting the stocking? What happens if they add

more weight to the egg? What happens if they use a different type

of nylon stocking? Make sure they change only one variable at a

time. Ask them to make a prediction before they test it out. When

they’re ready, have them test their final designs with real eggs. (Set up

newspapers below the jump site in case the eggs break.)

3

Club TM

TM

Meeting 3

Challenge TM

TM/© 2001 WGBH

Dear ClubZOOMers,

Rachel K. of Champaign, Illinois sent in this

challenge for you: Make a bungee jump

for an egg. The egg cannot break or hit the

ground. The egg must come within two inches

of the floor, and it can’t touch the floor. You

might want to practice first with a test egg

in order to get it right.

Give it a try!

pbskids.org/zoom

Blank Page

TM

TM

TM

sci

on™

Egg Bungee Jump

Wh

at

Yo

u N

eed

: •

nylo

n st

ocki

ngs

• eg

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rule

r•

plas

tic s

andw

ich

bag

• pe

nnie

s •

new

spap

er

1 T

hink

of a

way

to

use

the

stoc

king

to

mak

e a

bu

ngee c

ord

.

2

Mak

e a

test

egg

: Fill

a pl

astic

bag

with

pen

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unt

il it

wei

ghs

ab

ou

t th

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sam

e a

s a

real

egg

. The

n ti

e t

he b

ag.

3 T

est

you

r bu

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des

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with

the

tes

t

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t th

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side

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sto

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4

Evalu

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Whe

n yo

u’re

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,

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brea

ks!)

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Did

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do

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hat

happ

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if yo

u ch

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the

bun

gee

cord

len

gth

by

addi

ng

stoc

king

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cut

ting

the

stoc

king

? Wha

t ha

p-pe

ns if

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add

mor

e w

eig

ht

to t

he e

gg?

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wha

t ha

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you

use

a d

iffe

ren

t ty

pe

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hoos

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ne

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o ch

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(th

at’s

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ake

a p

red

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resu

lts t

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Scie

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Sco

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Whe

n yo

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op t

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gg, i

t fa

lls

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grou

nd b

ecau

se o

f gra

vity

.

As

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egg

falls

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wei

ght st

retc

hes

the

nylo

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he s

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stre

tche

s

beca

use

it is

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that

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gro

und.

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am

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stre

tche

s de

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s on

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weig

ht

of t

he e

gg

and

how

fast

the

egg

is fa

lling

. Se

nt in

by

Rach

el K.

of C

ham

paign

, IL

Desig

n a

bung

ee ju

mp

for

an e

gg s

o th

at t

he eg

g comes within two inches o

f the f

loor

with

out cr

ackin

g!

Try

It

Out!

pb

skid

s.o

rg/z

oo

m

TM

TM

TM

Send

your ideas to

Dear ZOOM

,Here’s what

happened when I designed an egg bungee jump:

Or, se

nd

a le

tter:

ZO

OM

Box 350Boston, M

A 02134

Don’t forget to include your

name and return address so

we can send you a copy of

ZO

OM

erang.

© 2001 W

GBH

Educational Foundation. All rights reserved. Z

OO

M and the Z

OO

M w

ords and related indicia are trademarks of the W

GBH

Educational Foundation. “PBS K

IDS” w

ordmark T

M PBS. U

sed with perm

ission. Funding for ZO

OM

is provided by the National Science

Foundation, public television viewers, and the C

orporation for Public Broadcasting. Any opinions, findings, and conclusions or recom

mendations

expressed in this material are those of the author(s) and do not necessarily reflect the view

s of the National Science Foundation.

All subm

issions become the property of Z

OO

M and w

ill be eligible for inclusion in all ZO

OM

media. T

his means that w

e can share your ideas w

ith other ZO

OM

ers on TV, the W

eb, in print materials, and in other Z

OO

Mw

ays. So, send it to ZO

OM

. Thanks!

Sen

d a

n e

-mail:

pb

skid

s.org

/zo

om

/sen

dit

Then instantly print out a

copy of ZO

OM

erang—a new

s-letter filled w

ith cast trivia and lots of fun Z

OO

M activities.

TM

Write

or d

raw here

. !

TM

Stay TunedClub

TM/©2001 WGBH

Meeting 3TM

At the next meeting, you’ll be challenged to:

Crack the Code Read the message by learning the Z Code. Here’s how it works:

The letters of the alphabet are reversed so that “Z” replaces “A,” “Y” replaces “B,”

and so on. Then, the letters of the message are replaced with the code letters, with no

spaces between words. For example, here’s how “SEND IT TO ZOOM” looks in Z Code:

HVMWRGGLALLN

To read the message in Z Code, find each letter in the coded message in the bottom

row and replace it with the letter in the top row.

HGRXPDZGVIGLZKVMMB

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Z Y X W V U T S R Q P O N M L K J I H G F E D C B A

pbskids.org/zoom

To translate a message in Morse code, find the letters that match the symbols.

Blank Page

TM

zinger™

Rest your ear on a tabletop, and have a friend tap the table with a pencil. What do you hear?

Lift your head up, while your friend continues tapping.

How do the sounds compare?

Try it again: Tap other surfaces with other objects.

Sent in by Abigai l A. of Fort Worth, TX

Hink PinksA hink pink is a pair of words

that rhyme. A hink pink for a

rodent dwelling is a mouse house.

Find the hink pinks for these things.

1. police chief

2. unusual cub

3. rosy beverage

4. bashful insect

5. noisy group

Listening Table

ClubZOOM Board

Meeting 3

TM/© 2001 WGBH

phenom™

TM/© 2001 WGBH

Try It Out!

Try It

Out!

ClubZOOM Board

Meeting 3

Answers: (

1. top co

p 2.

rare

bea

r 3

. pin

k dr

ink

4.

shy

fly

5.

loud

cro

wd)

Sent in by I an B. of Lincoln, NE

pbskids.org/zoom

pbskids.org/zoom

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85Egg Bungee

Club TM

funny™

TM/© 2001 WGBH

Second-graders from the Grove

School in Northbrook, Illinois,

are members of the ZOOMteam.

They baked 2,650 cookies

for 21 shelters for the homeless.

In the photo, Kristen, Nathan,

Michal, and Cole are rolling out

sugar cookies.

ClubZOOM Board

Meeting 3

TM/© 2001 WGBH

ClubZOOM Board

Meeting 3

Sent in by Andrea G. of Bol ingbrook, IL Hee-Hee-Hee-Hee

Ha-Ha-Ha-Ha!Ha-Why is basketball

such a messy sport? Because you

dribble on the floor!

Visit the ZOOM Web site

for ideas on how you can

volunteer. Then tell us what

you did, and we’ll send you

a free ZOOM Into Action

wristband and iron-on

T-shirt decal.

Join the ZOOMteam

!

TM

pbskids.org/zoom

pbskids.org/zoom

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