The MMS Blog

Balancing Act: Sixth Graders Create Mobiles that Represent Equations

When you enter IIA and look up the first thing you see are colorful, three-dimensional shapes hanging from the ceiling. These geometric mobiles were built by the sixth grade and are physical models of the mobile puzzles they created in class. Students Emily M. and Camille B. describe the project below. 

Mobile puzzles are pictorial representations of systems of equations that have different shapes whose weight add up to the number at the top.  The mobile branches off, and the left and right side beams weigh exactly half of the top number. The images below illustrate the concept well. Each beam can be split further to make the problem more complex. The challenge is to figure out the value of each individual shape by using logical reasoning and algebraic moves.  This is similar to an equation in that the expressions on both sides of the equal sign are the same. 

We also incorporated some lessons from earlier in the year into this project: In both science and math, the sixth graders studied “nets” of geometric shapes. The net of a shape is a pattern that you can cut out and fold to make a solid, three-dimensional shape such as triangular and rectangular prisms and cubes. We decided to fold nets and create different solids to help bring our mobiles to life.  

This project was a bit challenging but a lot of fun. We enjoyed helping other classmates figure out how to fold and attach shapes. We learned about mobile puzzles and how they relate to the algebra we worked on in class.  We also learned about folding nets, and that you needed to work carefully to get the tape to stick on the inside of your shape. One of the hardest parts was getting the mobiles to stay on the ceiling because gravity was against us. Another hard part was creating your own mobile problem because you had to figure out how to make different values for each shape while making sure the mobile was still balanced.



Posted on April 25, 2019 in