Egg drop project is always fun for kids. You design a structure to hold the egg and to protect the egg from breaking when dropped from certain height. The project can be designed for different age groups with various difficulty levels. For this one, we limit the design materials on straws, tapes and hot glue only. The goal of the project is for kids to learn physics science, design process, engineering while having fun. If you’d like to try with your kids or students, we have a free design process worksheet to help the design thinking.
Egg Drop Project Design Experiment with Straws
Before we start the design process, we did some online search to get some design ideas, then we tried the pyramid design first. Of course, it failed. The real learning happens when kids have to figure out what is wrong and how to improve. Read on to find out the winning design.
First Egg drop design with Straw – Pyramid
The first step is the make a pyramid shape that holds the egg snugly. For this holder, each straw is bent to the appropriate length, so the egg can staying in it without moving.
Then tape or glue the full-length straws along the edges of the pyramid holder, so each edge is extended with a straw to stick out of the pyramid vertexes. The goal is to have the extended straws bear the forces upon touching the ground, thus deviate the force on the egg.
We used tapes and hot glue to put all straws into the place we wanted.
The test result?
After the failure, we discussed the reasons. One thing we noticed was when the egg dropped to the ground, the side that landed on the ground was on 3 straws with the same length sticking out the 3 vertexes. This makes the connecting straws parallel to the ground. These parallel straws must have hit the egg hard.
With this realization, we started the next design.
Second Egg drop design with Straw – Unbalanced Pyramid
Based on the learning from the first failed experiment, we did a 2nd design to make sure all extension straws sticking out of the pyramid vertexes with a different length. But this time, the egg broke again. It was not as bad as last one, though.
We analyzed the causes again, and realized that pyramid is a not a good shape to start with. Because, with this core shape, the landing side is usually with 3 straws sticking out. As we learned in geometry, 3 points form a plane, this means the landing force are equally distributed among the 3 straws, and then transfer to the crossing straws connecting these 3. Although these crossing straws are not straightly parallel to the ground, they still push the egg when it lands on the ground.
The solution is to use a cube shape as the core to hold the egg. This way each side has 4 straws sticking out. The longest will be the one holding the force when it hits the ground. When only one straw is bearing the force, most of the force moves along the direction of the straw, thus little goes to the egg.
Third Egg drop design with Straw – Unbalanced Cube
Based on our analysis on the 2nd failure, a 3rd design was made. The center is a small cube to fit the egg. Then long straws are glued along each side of the cube. We made sure that each long straw extends out of the cube vertexes at a different length.
Can you guess the result?
The egg stayed as a whole, not even a crack!
Egg Drop Design Project Tips and Tricks
The key idea of a successful straw structure for egg drop project, from physics point of view, is to find a design that the straw will divert or absorb most of the forces, thus little force goes to the egg.
Lessons we learned from the project design process
Focus on the design process, instead of result. Use the design process worksheet to help you. You can download the design sheet for free at the bottom of this post.
Don’t expect others’ ideas will work for you. One of the sources we get our idea from is this Egg Drop Design YouTube video. The guy in the video made it look so easy to use a straw structure. We copied his idea, but failed. Do learn from others’ ideas. However the key is to think through the reasons behind each design and analyze the causes to fail or success.
More process and design tricks we learned through this project
Use plastic food wrap to wrap up the egg. If the egg broke, the egg white and yolk won’t flow or splash everywhere. This makes cleaning up a lot easier.
It is easier to use duct tape or washi tape to fix the straws together into shapes. Hot glue works well too, but it may not a good option for younger kids.
Regular tape doesn’t work well with straws.
As you can tell from the pictures, we found it helpful to double up the straws for each edge and the extension.
Have you tried egg drop projects with straws? What is your winning design?