## Wednesday, May 2, 2012

### 3-D Object Project

I'm currently teaching the Volume / Surface Area unit in my geometry class (10th graders) and for the most part, they have all been pretty convinced that it is easy (being that they have so many formulas). Therefore, I wanted to have my students thinking about the topic in a reverse way. I got this idea from something I saw on pinterest where someone had their students create a "pokey wall" by having each student make a pyramid. And I was further convinced that my students needed to improve their ability to go behind formulas based on a question I gave on their last test on the Area / Perimeter unit (Draw and label a trapezoid with area of 100). The question had about a 50% success rate with many students unsure as to how they could pick and choose various heights and base lengths.

Anyways, I gave my kids two days in class to work on this project. On the first day, I had students randomly draw (from my hand) what their 3-d object would be [I did this so I wouldn't get all cubes]. I did allow for students to trade with one another as certain objects had possibilities for extra credit. I informed the students that because of the size restrictions (the base area and volume had specific limits), they should spend the day figuring out side/radius/slant height values so that they could start building the next day. Many students struggled with the concept that they could assign random values to meet the size requirements. Also, students who chose more complex bases, realized that they had a few more calculations to solve before being able to construct anything. On the second day, a few students began their constructions with me (the cones were rather hard for students to grasp) while others continued to work on their calculations.

The project isn't due until next Monday but I have so far gotten back a few projects and they are looking great! So far, I've gotten a rectangular prism decorated to be a present (bow and wrapping paper included) as well as a Captain Crunch box. I've also gotten some very well done pyramids and cylinders. When I get the lot of them (30 students in one class and 22 in the other), I'll take some pictures and upload.

Until then, enjoy the rubric below!
3-d Object Project