In 7th grade, we started right away with physics concepts. These are some of my favorite areas of science! I love teaching Newton’s laws, investigating forces and computing the simple math equations that come with! My students however, don’t always seem quite as eager!
While discussing friction one day, I decided a design lab was needed to boost their interest level and understanding. Students knew friction slowed things down, but some were having a little trouble thinking about why friction is also helpful! Someone replied with a comment about parachutes, and instantly I had my idea.
After class, I frantically searched every drawer of my classroom for a little bag of these:
I had collected them at a 4th of July parade this summer, just in case I had a brilliant idea.
With just a quick search online, I found several activities that related to what I was thinking: A Slowest Parachute Contest. Teachengineering.org had this lesson plan already created! It was simple to put together, used simple materials and taught the concepts I needed it to. Winning! Although I did make a new, slightly adapted worksheet, I followed this lesson pretty closely!
This took my class two class periods, although both classes were shortened because of other activities going on that week. You could most likely complete it in about an hour if needed. The first day, students were given the challenge and the supplies.
- One army man
- A Plastic Bag
- Construction Paper
- Students were put into groups of three, and each group had to decide which material they wanted as their parachute.
- Next, students cut their material into a circle. I was not specific on the size of the circle on purpose. Part of the lab is to see if the area has an affect on the parachute’s performance. Some students used a compass to help draw their circles, which was a great idea. They also put a small hole in the middle of the circle of their parachutes, after some discussion over whether this was actually a good idea or not (it is…and after discussing, most agreed).
- Before attaching the parachute, students needed to calculate the area of their circle. Yay for the math connection! We used the formula r2 . Students needed to be reminded to measure in cm so we all had the same units! At the end, we compared our surface area to the times of the parachute drops.
- Students could then tape or tie their army man to their parachutes using string. It was interesting to see the various ways students did this-some army men ended up falling upside down!
Day 2 – Testing!
At the beginning of our second day, we had about 5 minutes to make last minute adjustments to their parachutes. Then, student groups sent one “dropper” at a time to drop their army man while I timed the drop.
Each group was given three drops. There were a few “do-overs” when the parachutes hit a desk or chair on the way down. The times were then averaged. Unfortunately, I didn’t get any pictures of this, since I was using my phone to time the parachutes!
After each group had completed their drops, we had a discussion. It seemed to us that a larger parachute did help, but it was not necessarily the most important thing. Also, it seemed like the plastic bag material worked the best, but newspaper also worked well. I’m sure if we did this again, those results may vary.
Overall, the lab did seem to help students understand friction, especially air resistance. This activity was such an easy one to add last minute. Students were engaged, asking good questions about their designs and most importantly, gaining understanding of friction!