## Friday, June 7, 2013

### 3-D Surface Area and Volume Projects: 2013 Edition

Here are the 3-D project photos from this year. I kept only the yellow tower and the red-and-yellow rocket from last year, so everything else on the shelves is new! As usual, they had to calculate volume, surface area, and draw 3-D designs and 2-D nets. Even though concavities were optional, many groups decided to build in concavities into their designs / calculations this year.

Afterwards, our tests were not easy, but the kids did quite well! In fact, the student who did the "star" project shown in the first picture (5 pyramids connected to a pentagonal prism, with a rectangular prism concavity) got 100% on her test, which made both her and me totally excited!!!!

Among other test problems, I offer you these two to try with your students. These problems integrate the flexible application of formulas with the necessary skill of visualization of volume and surface area. For an easy differentiation, you can replace one of the sides with x, and ask them to find an abstract formula for the SA or volume.

Calculate volume and surface area:

Calculate just surface area.
(Only standard circle equations for area and circumference are given.)

PS. Bonus points for me, for drawing this last solid on the computer in a way that is kid-friendly!! Even though I am pretty used to drawing shapes on the computer, this one was particularly challenging to visualize in a way that is not overly detailed. Normally I would show all the dashed lines in the back that are hidden from view, but that looked too confusing, so I had to take them out. I also decided to shade it this way, in order to hint to the kids that the two light gray sections are connected around the back of the (partial) cylinder....