Science Fair Project on Arches and Domes: How Many Books Can Eggshells Hold?

My son, Brendan, is fascinated with building things and wants to be an engineer. For one of his elementary science fair projects, I adapted some ideas I'd seen at a teaching conference twenty years earlier about challenging kids to build things out of index cards which could hold a brick.

Brendan loved this project and learned a lot about engineering principles and what makes a strong structure. This particular project had two parts to the experiment, and we also had him do a research component by looking on the web to learn about domes and arches. You could do a project with only one of these experiments or devise something similar to the sugar cube experiment using blocks.

Can Eggshells really hold up a Stack of Books?

I should add that after this time Brendan became a whiz at building with Legos and is still involved in engineering projects for the Junior High Science Fair. He went to state last year and he just finished his project for this year. Whether or not your child has to do a science fair project for school, they may enjoy doing this experiment which really is a lot of fun!

Question: Why are Domes and Arches able to stay up without falling down?

Experiment One: How Many Books can eggshells hold?

Materials:

• Eggs
• Books (same size books are best)
• small scissors
• Table

Method:

1. Create the half eggshell "buildings.": A parent may need to do this part, but you can certainly let a child try too. Carefully poke a hole in the egg with small sharp scissors. Next, cut around the egg as smoothly as you can. Do this until you get four eggshell halves which are the same height (you may need to shave down edges until they are the same). If an egg cracks during the process, you will need to use another egg. For the experiment to work, the eggs need to have smooth edges without cracks onto the surface.

2. Make sure eggshells are the same height: Put four eggshell halves down on a firm table surface. Put one book on top to make sure they are all level.

3. Hypothesis: Make a hypothesis of how many books you can stack on your eggshells before they break.

4. Test your Hypothesis by putting books on your eggshell houses. Put them on carefully and slowly so that you don't use extra force. Take pictures as you go for your poster.

5. Results: When your eggshells start cracking, your experiment is done. See if your results matched your hypothesis. Write down what you learned.

Research: Look at some of the resources on this Hub about building, arches and domes. Look up on the Internet some information about domes and arches, or find a book at the library with information you can study. Find out why these shapes are so strong. Look for examples of famous domes and arches. Write down what you learn. Can you find any examples of domes or arches in your neighborhood or town? You might want to draw or take pictures of them for you Science Fair poster.

Experiment #2: Can I build an Arch?

Materials:

• Paper and pencil
• Sugar cubes, boxes, blocks or other square shapes
• Table

1. Hypothesis: Do you think you can build an arch? how many cube across? How many different arches can you design?

2. Building: Using the sugar cubes, see if you can build a bridge or arch which stays together just by the force of gravity. Try different designs. How high can you make your arch? How many sugar cubes across? Challenge other people in your family to try.

3. Gathering Information for Poster: Take pictures and draw your designs on paper for your poster.

4. Conclusion: What did you learn? Were you surprised? Was building an arch easier or harder than you thought?