RESOURCES FOR TEACHERS: Pipe Cleaners, Plastic Straws, and Paper Clips – a Middle School Design Challenge
[NOTE: This article appeared in the August 2013 issue of Tech Directions magazine, and is re-printed here with the written permission of the editor. Published monthly August through May, Tech Directions serves teachers and administrators in technology, applied science, and career and technical education.]
By Martha Vanloon and Harry T. Roman
Ms. V. is a 6th grade teacher at the Thomas A. Edison Middle School in West Orange, NJ. Harry is a retired engineer and inventor. They have team-up to motivate students to think outside-the-box in true Edison fashion.
The school is close to the Thomas Edison National Historical Park, so inspiration for invention is just literally down the street about a half a mile.
Here is a story about how Ms. V. and her students built some very interesting structures out of simple materials like pipe cleaners, plastics straws and paper clips.
Ms. V. prepared her students for the design challenge by discussing how large structures are designed and built, showing pupils some of the great structures of the world. The students were already familiar with Harry as he has been to the school a number of times already to talk with the students about his many inventions and engineering career. Each student had to prepare for the challenge by developing a plan and diagram for how they were going to approach the actual design using the assigned materials.
Teams of 2-3 students were assigned and each student was given necessary materials for the challenge. A total of five class periods took part in the challenge involving about 200+ students. Each team had one standard class period to complete the challenge.
As each team began their activity there was a variety of reactions from the students as they realized they were on their own and able to make their own decisions about how to solving the challenge. Some did seem to look for “the right answer”, only to learn quickly from both Ms. V. and Harry, that there are no right answers, just a design they are in charge of conceiving and carrying out. Those students and teams that spent time thinking and planning the exercise before-hand, generally had the most success and confidence in the challenge, immediately teaching the students the importance of planning and organization. As usual, with design challenges such as this, there is often a good deal of on-the-spot engineering and iterative thinking to get the design to work.
Students quickly learned that sticking pipe cleaners through straws can significantly improve the rigidity of a pipe cleaner, making it a strong structural element for a foundation for the tower. The whole gist of this exercise was to build a tower as tall as possible that could support a golf ball that hung down from the tower at about 75% of the tower’s height.
There seemed to be the realization among students that a triangular base had some interesting virtues over a standard square or quadrilateral base. Students who built four-sided bases learned that such structures generally needed some form of bracing to keep the structure from twisting or collapsing under the weight of the golf ball. Students display an interesting array of bracing techniques. Those who built their bases out of pipe cleaners only, soon learned a lesson about building on weak foundations.
Interestingly, many of the teams built a small tower first to show they could suspend the golf ball, and then tried to increase the height of the tower to get the whole structure as tall as possible. This presented some interesting design problems as they now had to improvise a bottom section that could mate with the completed top section….not always obvious to the exuberant students. One team worked on a design that drew its inspiration from the Eiffel Tower, and did manage to achieve a nice height with their design. The tallest structures reached into the 50-65 cm height range, along with some interesting and artistic top creations by the students!
In the coming months, Ms. V. and Harry are planning to do some additional activities with the class, hoping to give the kids a look at how engineers conduct experiments, collect data, graph the results and draw conclusions from what they discover.