2nd Graders designed their own buildings, inside and out. These were really fun. The students enjoyed designing the inside the most.
First we folded our paper so that we would have to parts of the front that would open at the center revealing the inside. Next, students drew the exterior of their buildings. I had to really emphasize that the sides of the building had to be the sides of the paper. Some students did not get that and we had to do a bit of taping, but hey, we role with it. After drawing the exterior of their building, we cut the negative space at the top off so that the inside of our buildings would have the same shape as the outside. The previous processes actually took two class periods of 50 minutes, given time talking about architecture and so forth.
After students had finished designing the exteriors of their homes, came the interiors. We discussed what kinds of things we would have inside of a dream house. All sorts of ideas came up. Some of the best ideas were rooms of trampolines or filled with balls, underwater rooms, you name it. students then colored the inside of their houses.
Materials for this one were simple; construction paper crayons, scissors, and 9x12" construction paper. When they were all completed we lined them up like row houses, creating a little neighborhood.