In May of 2014, I was invited to Elmwood Village Charter School to speak to Ms. Schneekloth’s second grade class about simple machines and forces. Knowing fully well that I would be working with students under the age of 10, I knew I would be working with sharp minds but short attention spans.
To my absolute surprise, these kids were the brightest group of young students I had ever encountered.
Keeping this in mind, I decided to bring in my homemade cotton candy machine as the centerpiece for this lesson.
My homemade cotton candy machine made from a large stew pot, a tin can with holes drilled in it, a hobby motor, a 9V battery, a burner and some other pieces found at the local hardware store.
Needless to say, the kids were thrilled to find out that not only would they be learning how a simple cotton candy machine works, but also get to sample the final product of this experiment: the cotton candy!
I organized and presented my lesson in 3 phases: discussion, conceptual and interactive.
Discussion
This phase presents 2 – 3 basic topics emphasized throughout the lesson. Depending on the grade level and age group, this phase can be adjusted to accommodate the complexity of the material.
The basic principles we discussed were centripetal force, friction, and electricity.
I made sure my explanations were short and peppered with brief intervals of student questions and feedback. This worked very well and helped maintain their interactivity and interest.
This phase was really successful because the more I spoke, the more their hands seemed to go up! To me, questions are always a good sign of attention and learning and there were plenty of interesting questions asked throughout the lesson.
Conceptual
The conceptual phase emphasizes conceptual learning while creating multiple opportunities for the students to move and interact with each other and the environment.
In this phase, I had the kids stand up and form two circles: a large outer circle and a smaller inner circle.
In the case of the cotton candy machine, the outer circle represents the large pot that the candy floss collects on when it is ejected from the inner container (the heated tin can with holes in it). The inner circle is composed of about 4 kids who face the outer circle while holding plastic coffee containers containing pink yarn.
The pink yarn represents what happens to the melted sugar when it shoots from the heated center can and cools midair.
The kids in the inner circle begin to spin together in a clockwise direction while holding the small coffee containers. As they do, they toss the ends of the pink yarn (with small weights tied to it) to one of their fellow classmates in the outer circle. This represents the candy floss cooling and attaching to the pot (the outside circle).
As the inner circle continues to spin, the pink yarn begins to tangle and form in the same way that candy floss forms in the machine!
Everyone is getting tangled!
In the end, we had a tangled web of pink yarn which gave the kids a more conceptual idea of how the cotton candy is going to form when it shoots out, cools midair, and attaches to the sides of the outer container.
I made it a point to continually remind them of the centripetal forces we discussed in the discussion phase of the lesson to further reinforce the concepts. However, the most important thing of all was that the kids were having a great time forming and untangling themselves from the web of pink yarn.
Interactive
The final and most entertaining phase of the lesson was the interactive phase. Here, the students actually got to see how the machine worked.
Piece by piece, I explained the machine and its parts, as well as how these simple little parts contributed to the machine’s overall function.
Demonstrating the use of wires to create the circuit that will turn the machine’s motor on.
After a brief description of the parts, I then showed the kids how, after pouring the sugar into the center tin can, I would melt it with the burner and then turn the machine on to make the cotton candy.
Melting the sugar in the center tin can with the burner.
In capable hands, this process isn’t dangerous but, nonetheless, I made sure to set a good example by wearing a lab coat and safety glasses.
Notice how the smoke comes from the center can. This indicates that the sugar is starting to melt.
A lot of the kids seemed to be nervous about the fact that I was lighting the burner with a sparker. After assuring them that I would never bring anything that I felt was dangerous into their classroom, I took this opportunity to discuss lab safety and the importance of understanding the tools and materials we were working with.
Finally, I asked all of the kids to gather around me while I repeated the process of meting the sugar and creating the cotton candy.
In the end, we had some great cotton candy that every kid got a chance to sample. Unfortunately, I didn’t get a chance to take pictures of the candy floss because the kids ate all of it!
This is the part where I was supposed to take pictures of the cotton candy but they ate it all!
Since I had a few minutes at the end of the experiment, I opened the floor for questions and answers. They asked everything from how the burner works, to why cotton candy comes in different colors, and even how old I was.
Questions and answers.
In the end, this turned out to be a great experiment and one that I hope to repeat with other classes in the near future.
Special thanks to:
The University at Buffalo Machine Shop for allowing me access to their staff and the machinery used to create the cotton candy machine.
&
Ms. Schneekloth and her wonderful second graders for allowing me to teach them about physics and engineering!
Physics Schmizx! 
