Thursday was the first day that I met with the students to begin our design project on balance and mobiles. I started the hour off by presenting a few fun facts about myself so the students could get to know me a little. To start off the lesson on balance, I first asked the students what they already knew about balance. I gave a few examples to get them thinking. Deb did a great job helping me with the students. She implemented some classroom techniques that she uses daily and instead of the students raising their hands, they talked with their family tables about what they already knew about balance. I was able to walk around the classroom and listen to the students talk among each other. Some comments from the students inlcude:
"there needs to be an even amount!"
"a tightrope walker needs to balance their arms!" (student was holding arms out demonstrating to other students how the arms need to be level to be balanced)
I introduced mobiles to the students and asked them what prior knowledge they already knew about mobiles. Students pointed to mobiles that were hanging in the classroom created by the second graders, and they said that they needed to be balanced. They remembered making these mobiles when they were younger. We proceeded to the computer lab to experiment with a website I found on mobiles. This gave the students a basic understanding of a mobile (if they didn't already know what a mobile was) and the mobiles could be constructed as simple to complex with this program. When the students were working with the computer program, they started to experiment with the number of "branches" or levers that the mobile had. This increased the complexity of the mobile. Students typically started building the mobile with objects that were the same and then moved to using a variety of objects on their mobile.
The students noticed a "balance" button that is available for the user in case they can't balance the mobile, but the students became bored with this command and would opt out to not use it and balance the mobile themselves. The students understood that the mobile was balanced if the levers were level. The mobile would only be "set in motion" (another command) if it was balanced, which was another indication to the students that their mobile was in balance or out of balance.
The website for this mobile program is:
After the students were able to work on the website for a while, we went back to the classroom and looked at some examples of mobiles. I helped the students understand the parts of a mobile and how mobiles balance. I then had the students look at some artistic mobiles and we talked about what people might like or dislike about these mobiles.
Some of the comments the students gave were:
"I don't like them because they are not so organized." (too abstract)
"I like them because they are different and unique."
"I think about mobiles over cribs (when the student looks at these images) because the shapes are colorful, not plain, different, not the same."
"I like the one that has one heavy ball on one side and on the other side there are other objects that are lighter than the ball." (the ball is heavy; the smaller objects, individually, are light, but when combined they equal the weight of the ball)
"I like them because they look simple, but the balance is really complex."
Now that the students had basic knowledge of what mobiles are,the students did a final activity during this lesson and I asked them to sketch a mobile that expresses something about themselves and that is possible to build in two hours with the materials they decide to bring. The rest of the hour, the students sketched and I walked around the class observing visually and audibly what the students were planning. This mobile they sketched is the mobile they will try to make in the next couple of classes.
As I spoke with students about what they were sketching, one student really surprised me. He drew a mobile that had three large circles on one side, and six smaller circles on the other. I asked him about his sketch and he told me that the three balls will need to be heavier than the small six balls in order for them to balance. I walked away and then noticed him pull out his calculator! Deb told me to come and see what he was doing and he told me that the three large balls equal three ounces, so each ball would be one ounce. Then he calculated how heavy the six smaller balls needed to be in order to balance the mobile! He concluded that the six balls need to be .5 ounces. This student is well on his way to developing a balanced equation for his mobile! He was using a very logical approach to the mobile, where other students were using a more artistic approach.
Other students in the class had mobiles that had multiple levers, multiple objects, one heavy object on one side and smaller lighter objects on the other side, and equal objects on each side. Each student was assuming that their objects on one side would equal the objects on the other side.
At the end of the class, the students brainstormed what materials they will need for their mobiles. For the levers, they will use straws, sticks, closehangers, popsicle sticks, or wire. For the hangers, they will use yarn, string, ribbon, old shoelaces, paperclips, or rubberbands.
Deb and I were able to meet after the lesson to discuss how it went and what we want to include in the upcoming lessons. We decided that we want to implement the Plan Do Review process more. It was clear that the students were assuming their mobiles would balance, and we need to make sure that the students understand that their mobiles may not necessarily balance and it would take some trial and error to get their mobile to balance. This way the students won't feel discouraged when they discover their mobile won't balance as planned. We also want the students to start experimenting with the location of fulcrum, length of string, and weight of object. The students will be able to work with their mobile, make a change and document what is happening. This process could be continued until the student felt satisfied with their mobile. I will be introducing Alexander Calder during the next lesson as well so the students can learn about his art process.