# 3D Printer in Math Class

One of the units that my seventh graders work on is Stretching and Shrinking from Connected Mathematics. This unit works a lot on scale factor having students enlarge and reduce figures. In this particular book they enlarge and reduce the Wumps. Two Common Core Standards that are a focus of this unit are 7.G.1 I can solve problems involving scale drawings of geometric figures, including computing actual lengths and areas from a scale drawing and reproducing a scale drawing at a different scale and 7.G.2 I can draw freehand geometric shapes with given conditions. On page 33 of Stretching and Shrinking there is a picture of a 3D model of Chicago at a scale of 1:600 it also talks about how they made this 3D model. During this unit I bring in match box cars of my son’s and we talk about the scale factor used to make these.

I happen to live in the lovely state of Iowa and this wonderful state has AEA’s (Area Education Agencies) that work with schools. The area that works with my school is Greenhills (use to be AEA13). Since I started teaching in Southwest Iowa Greenhills has always provided math teachers with great PD and wonderful technology. One of their newer technologies is a 3D printer and scanner that they allow school districts to check out for a month at a time. When I found that Greenhills had this new technology for check out I was informed that they were already booked up for the year. This year I called to see if I could get the 3D printer and found out that it was free the month of January.

I thought that this would be a wonderful way to connect real-world opportunities to something that we do in math. I also thought it would be a good way for us to get some STEM into our building. I had no idea how to use the 3D printer or scanner. I was naïve and thought you could just scan a drawing and it would print it in 3D. I did some research and found that students would need to create drawings in a 3D program. I asked my tech guy at school if he could download SketchUp onto a cart of computers for students to use.

I decided that I would take a week and allow my advanced math class the opportunity to explore SketchUp and see if they could create some 3D objects to be printed (ended up being about 2 weeks). I informed the class that I knew little to zero about SketchUp and that they would have to just try it out.

After the first day of many questions from students I was not sure if we would be able to do this with me not knowing much about SketchUp. My students blew me away with how they preserved. They would create something and if they didn’t know how to do something they would Google it. We then went ahead and starting printing objects. We found that there were errors in their drawings so they would go back and make corrections so that we could print again. These students never gave up.

What did we learn? We learned that it takes a while to print something (anywhere from 15 minutes to a few hours). We also learned that you can’t be afraid to try and mess up and begin again. Students also saw how things can be scaled up and scaled down when printing. Some students found that they didn’t really like doing this and some students found a new interest or a career path they had never thought about. Students also learned how much a 3D printer costs along with the filament that is needed to create objects.

It was amazing to see students lined up in the morning to see what was going to be printed along with fellow staff members. The band instructor at my school was very excited about the 3D printer and had us printing pieces of band instruments. One such piece was a clarinet mouth piece. After it was printed the band instructor added cork to the pieced and then played the instrument. It really worked!!! The industrial tech teacher designed some pieces and had us print those off also. He also had his students create Lego pieces to be printed off.

My other math classes saw how objects could be scaled up or down. I did not provide them with the opportunity to create using SketchUp as I didn’t feel I could take the time. I heard that some students were not happy with me for this so I informed them that they could work on Sketchup during homeroom and if they created something to print I would print it off for them. Some students took me up on this offer. Other tried but when they found out I was of no help in learning the program they gave up.

I have talked to my principle about getting a 3D printer and offering an elective class for next year. At first he was not so sure about the idea. My math students worked on creating a proposal for the principal. I will continue to work on that proposal and we will see where we can get. I think this would be a wonderful opportunity to bring STEM into our school. I also think we would be surprised at who would sign up for the class.

I have talked to some of the people who work for Greenhills and mentioned that it would be nice if they would offer a class on SketchUp or some 3D program for teachers over the summer.

Would I do this again with students? YES! I would like to get the 3D printer reserved for next year and have it in the classroom closer to the time we are working on Stretching and Shrinking.