Creating Tin Men to Explore Surface Area Project

I read about the amazing Tin Man project on Elissa’s blog Misscalcul8.  Please go there and read all about it in more detail!   I had to duplicate it for my 6th grade students.  They love being creative and surface area is tricky.

At their request, I let them make a tin man or animal.  The students chose their materials (they had to have a cylinder, a rectangular prism, a sphere, and a cone).  They then had to measure their materials and find the surface area of each item.  (My Tin Man Project Worksheet).  After the surface areas were calculated, they added it all up to find the total surface area of their tin man and how much foil they would need to completely him.  I created a Google Spreadsheet to automatically check all of their answers according to the measurements they had recorded.  This was essential for grading ease since every student had different materials and thus different measurements.  Then, they taped their tin man together, measured and cut the foil, and covered their tin man/animal in tin!  After they finished, I had them do Elissa’s reflection as well.  To save paper (and printing issues that students always have), I uploaded the questions to Google Documents.  Students had to copy the document to answer the questions, and then share it with me for grading.

A best aspect of the project was applying the aluminum foil to their tin men.  The students had calculated how much foil they needed to cover their man using surface area.  Once cut, if the amount of foil was too little or too much, they had to meet with me to talk about why this happened.  It was math in action!

Another great piece of the project was coming up with how much foil to cut.  They had to take their total surface area and divide it by the width of the foil roll (30 cm) before cutting the foil.  I made them figure this out before cutting the foil to deepen their thinking about area.  They then had to talk about why they divided my 30 in their reflection.  It was great to see that every student did understand why they divided by 30.

This project took longer than I thought it would, but was worth it. On the unit test,  my students scored better on surface area than on volume, even with the Play-doh activity!  Their biggest challenge were actually applying the foil to the tin men.  Next year, I will have them apply the foil first, then tape their tin men together.  They also wanted more time to decorate their tin men, but I had too much I wanted to squeeze in at the end of the year to give them an extra day.  Next year I will try to build in one more day.

I can’t thank Elissa enough for this project idea OR all of the help and suggestions that she gave me via email.  I love all of the fabulous math teachers in my PLN and am such a better teacher because of them!  Reach out teachers and connect with each other on Twitter.  Read their blogs, try their ideas.  It makes teaching a blast, and the students love it.  Everybody wins!

** Edited 4/27/16:  I added the Google Spreadsheet to check the formulas.