My science co-teacher and I switched roles at the semester (about a month ago). During the first semester, I lead grade 4 while she assisted, and I assisted her with grade 6; now I’m leading grade 6 and assisting in grade 4.
Grade 6 is studying the basics of astronomy right now, and I wanted to have a fun opening to such an exciting topic. The first lesson of this chapter happened to fall on the day when I was observed by Dr. Narumon, the head of the science department. I love to take a risk and try a new, engaging lesson on the days when I’m observed. This is a risk, of course, because that means I’m doing a lesson I’ve never tried before, but it’s more fun.
[I need to pause right here and just exhale. I cannot emphasize enough how lovely it is to get excited about being observed. At my current school, I see observations as opportunities to show what I’m capable of and to receive meaningful feedback. At my former school, observations by the principal were 100% dreaded. I cried after every single one and was always left feeling inadequate. I was a new teacher, so I had a lot to learn, but let’s just say that the delivery left much to be desired.]
OK, back to the lesson. I decided to have my 30 students, in groups of 5, make scale models of our Solar System (including Ceres to represent the Asteroid Belt and Pluto out of pure nostalgia) using toilet paper. I adapted my lesson from this one by the Astronomical Society of the Pacific and this one by The Center for Science Education at UC Berkeley.
The point of the lesson is to show how vast the solar system is. If you ever see a poster of the solar system, you know that it’s definitely not to scale because in order to show Neptune and Earth on the same piece of paper, you’d need a piece of paper that is several meters long. Or if you could fit them, Earth would be such a small dot, you wouldn’t be able to see it without a magnifying glass. A roll of toilet paper, though, can allow for great distances to be unrolled before one’s eyes.
The scale we used was 1 piece of TP = about 30,000,000 kilometers; Pluto ends up on the 200th piece! I used UC Berkeley’s printouts of the planets and the Astronomical Society’s table of distances and number of TP pieces to scale. We went outside and walked to where we planned to set up the six models — the football field — but we found students practicing their dance routine for Saturday’s school fair. My co-teacher and some students were quick to figure out a replacement location: the basketball court. My co-teacher and students were also super helpful with troubleshooting things like the wind and the fact that the cheap rolls of TP I bought had only about 150 sheets.
I felt like I had done a good job introducing the topic, accessing prior knowledge, and giving kids specific jobs to prevent slackers from slacking and overachievers from dominating their groups’ work. So far so good. Then the wind came up, so my co-teacher ran and got Scotch tape and a student ran to get scissors for the dispenser-less tape, and other students began using their shoes to hold planets and toilet paper in place. These kids have such wonderful flexibility and ingenuity, except the one group whose entire model up to Mars blew away…oops! Dr. Narumon, meanwhile, was watching other students work together to count out the correct number of TP sheets between each of the planets (and somehow missed the big blow-away).
One group was working quite a bit faster than the others, so they figured out the other dilemma first: the roll would only allow them to get to about Uranus, but they needed 50 or so more sheets to make it to Pluto. They figured out that they could double their TP length by peeling apart the two plies! They made it to Pluto! Another group ran out of space due to a tree at the edge of the basketball court, so they placed Pluto about a meter up the trunk of the tree. Again, very crafty!
Time was running out, and only two groups actually finished. I decided to use the two groups’ finished models as talking points for a closing discussion. I asked the students to sit on the shady side of the basketball court, and we had a quick but fruitful discussion. Kids came away with exactly what I’d wanted them to: the solar system is crazy huge, distances between the planets are much greater than they thought, and the relative sizes of the planets are surprising too. In addition, models and illustrations of the solar system that fit on a standard piece of paper or even a large poster are never actually to scale, meaning that even our sacred textbook is inaccurate!
After the lesson, Dr. Narumon smiled, touched my shoulder, and said, “Great lesson!” So while there were some hiccups, my supervisor liked it, my kids liked it, and I liked it. It was a great learning experience for me. The next time I do this activity, I’ll be able to take preventative measures against the issues we faced. Yay for living and learning!
If you’re an educator and would like the worksheet that I made for this activity, leave your email address in a comment!