Tall Tower Challenge

 

The Burj Khalifa is currently the tallest building in the world, but there are many tall buildings across the globe that are considered to be architectural wonders and there is a constant battle to build these structures that are taller and taller.  While there are a variety of materials that I have seen used to challenge students to create tall structures, I have found some very simple materials that allow students to build towers from floor to ceiling.

Material List and Notes - 

• Index cards

• Masking tape

• Coffee stirrers

• Newspaper

• Tennis balls

• Scissors

Prior to the Challenge - 

Before students get into the meat of this challenge, I have them discover the strength of shapes.  The challenge is to use 4 index cards and 12 inches of tape to build a structure that can hold a textbook at least one inch off the table.  After students are able to do this, we start adding more textbooks until the structure crumbles.  I do allow students to use scissors, but I do not allow them to get additional material to add to their structure.  If their idea does not pan out, they start over with new materials.  This works best if students make cylinders of equal height, but let them figure that out!

After the students have time to experiment we talk about the 3 basic shapes - square, triangle and circle. Students should have discovered that circles are the strongest - but why?  When the book is placed onto the structure, weight is pushing downwards onto the structure.  On circles the weight is equally distributed, whereas with squares and triangles the weight is not equal plus there are corners.  Corners are weak spots - circles do not have any!  So why do we not always use circles?  The material used comes into play.  Cement is easy to form into circles while wood is more challenging.  Squares are easy to build but are weak.  Turning squares into triangles is easy by adding a diagonal brace or two!  I do this section all through discussion and guiding questions.

The Challenge - 

The big challenge is to build the tallest freestanding tower that can hold a tennis ball at least one foot off the ground.  Each group gets newspapers, masking tape and 20 coffee stirrers.  There is a video at the top of this post of how to make a paper stick to be used for this challenge.  Students then use those sticks to build their structure - keep reminding them about strong shapes.  They will ask if they can try and get the straws out of the paper tube and I tell them “go for it”;  I am terrible at getting them out but the kids are always really good at it.  

I usually give kids 2 days - getting the hang of building sticks can be a challenge at first.  At the end of the second day we test the structures.  Who has the tallest freestanding structure with a tennis ball at least a foot off the ground?  If there is a tie we look at the location of the tennis ball;  the higher the tennis ball the more difficult it is to achieve.

Wrap-up

Some groups will be successful while others will struggle.  Some groups will start off strong only to have a catastrophe at the end.  I do not assign points to students for the actual structure (although I do not tell them this), but rather from the analysis of the process and what they have learned throughout.  Here are the questions that I have students answer - 

• If you had a chance to do this project again, what would you have done differently?

• Do you think that this activity was more rewarding to do alone, or would you have preferred to work as a team?  Why?

• Do you think that once a building is designed and approved for construction that many aspects are changed during the building process? Why or why not?

• Explain why circles are stronger than triangles?

• Explain why triangles are stronger than squares?

• Based on the information that you have gathered and observed during this challenge - why do you think the Leaning Tower of Pisa is leaning?

• If you could have used an additional material (glue, wood sticks, etc.) which would you choose and why?