Discover Engineering in Central Texas

Grade Level:  Middle School, 5^th-8^th

Related classroom topics:  Problem Solving

Supplies Needed: 

For a classroom of 20-30:

·        30 helium quality balloons

·        Tank of helium

·        String attached as seen in diagram

·        Masking tape

Procedure: 

1.      Attach 6 strings to a center point as shown in diagram.    

2.      Allow 6 students at a time to problem solve possible ways of making their balloon stop closest to the center. 

3.      The students can change their design considering over inflation, under inflation, friction, angle of attachment. 

4.      Let students race in 6 person heats.  Discuss the experiment afterwards, examples of possible questions follow:

a.       What can help you win this contest?  (List three observations)

b.      Is it better to inflate the balloon a lot or a little and why?

c.       Is it better to attach the balloon parallel to the straw or at an angle? Why?

d.      Does the position on the straw matter?

e.       What function is being served by the string?

Extensions: Given time, allow students to redesign their ideas to optimize the time it takes their balloon to reach the center. 

Related topics you could discuss:  Problem Solving, Air Buoyancy

Hints/Tips:  Think about the weight of helium in comparison air.  Test out this experiment on your own before demonstrating it in the classroom.  Ask the teacher for any possible supplies of helium at the school.