Last year, when I taught 3-D topics at the end of the year, we: watched Flatland (which we did again this year... the kids LOVED the movie and were bubbling with opinions about the existence of a 4th dimension); did some awesome computer investigations (which we are still going to do this year); and we also did a bunch of textbook practices involving volumes and surface areas of composite 3-D solids. This year, I scrapped the in-class algebra practices, am assigning just a few problems as Do Nows and daily homework, and instead we are doing an in-class project where kids design and build their own composite solids, for which they'd have to calculate the volume, surface area, and draw related nets.
My regular kids have already: learned how to keep track of surfaces (in computing surface areas); figured out how to find the height of a cone or pyramid given its slant height; reviewed how to calculate volumes and surface areas of a prism/cylinder or a pyramid/cone. In terms of their projects, most of the groups in my regular Geometry classes have gotten their 3-D designs and dimensions and nets with dimensions approved by me, and some groups are starting to cut out the nets to create the 3-D shapes.
I am excited! The regular projects are on track to be finished by Friday. (Honors kids will have a few extra days, since I want their efforts this week to be focused on polishing their Geometry magazine articles.) Their designs look pretty awesome and are all very different; the kids are practically tripping over themselves with excitement over this last project. Pictures to come!