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.  

Volume of 3D Shapes with Play-doh

When my students are excited about what they are doing in class, they are engaged.  They will listen and best of all, learn.  The kids were ecstatic when they saw the Play-doh.  They couldn’t wait to get their hands on it!  The benefits for learning were amazing.  All I had to say was “Remember the Play-doh?” and they knew what to do for any volume problem.

Supplies per student:

  • One fun-sized Play-doh
  • Ruler
  • Plastic knife
  • Ruler

Many of my students had heard somewhere along the way that volume equaled length times width times height.  So, I started by having them make a rectangular prism out of their Play-Doh.

Once it was made, I had them draw a picture of it in their Geometry Booklets.  Then they measured and recorded the length, width, and height of their prism in centimeters.  Next, I had them cut their prism into 1 centimeter lengths.  They observed that the cross sections were squares.  I had them find the area of this square.  We talked about how many slices they had.  So if their area was 6 centimeters squared and they had four slices how could they find the volume of the box?  They quickly deduced that they needed to multiply the 6 by 4 to arrive at 24 cm cubed.

I repeated this for a cylinder and a triangular prism.  We observed what the cross sections were, found the areas of our cross sections, and then found the volume.  To sum it all up, we talked about how volume of a prism or cylinder is the area of the base (cross-section) times the height (number of slices).

It was so much fun!




Turning Words into Math – Graphic Organizer

I made this graphic organizer to help my students quickly (and visually) reference the math symbols that words often translate into.  I had them glue it onto the back cover of their notebooks for easy reference.  The words are not centered on the page so that the paper can be easily cut down to fit onto spiral bound notebook pages.  The PDF file is below.  Thanks!  🙂

Words Into Math Graphic Organizer and Word Bank

Creative Commons License
I Speak Math Materials by Julie Reulbach is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License.
Based on a work at

Smarties for My Smarties – After School Math Help Incentives

Once a week I offer after school math help for each subject.  After school math help is great because it’s a small group so I can focus on exactly what each student needs.  Students come to after school help if they have been absent and want to catch up (very needed in winter months), If they would like help on the current topic, or if they would like to do their homework with me.

Unfortunately, after an 8 hour school day, no one is very excited about after school math help.  In fact, I think I heard someone say, “Dreading it.”  So, I decided to spice it up a bit for the students (and myself) by adding a bit of after school sweets to after school help.  I figured if they decided to come to after school help, they deserved a little sweet treat!  Each student that comes to after school help gets a roll or smarties and a tootsie roll.  This may not sound like much, but it’s a fun treat at the end of a long day (and the beginning of 45 minutes of math).  The little bit of sugar gives us all just the edge we need to help our brains make it through 45 more minutes of learning.  But, it does more, with the addition of some music, a little candy makes it a lot of fun!  Today my fabulous 6th graders even talked me into a bonus – one single smartie for every question they answered correctly.  I had a blast with them, and they even came up with a cute slogan, “Smarties for Smarties.”

After school help today was FUN, the students were awesome, and I’m really looking forward to spending more Wednesdays with my amazing 6th grade Smarties.

Update:  Today when I came into class this was on the board.  I’m just happy to know that my students enjoyed it too.  🙂