This is a STEM lesson for applying perimeter and area. The students can measure, sketch, calculate and choose materials to give their classroom a makeover. Students work in groups to add flooring, paint, crown molding, and baseboards to their classroom using what they know about area and perimeter as well as measurement.
When I did this with my 4th graders, I brought in samples of carpet, wood flooring, various paint chips, baseboards and crown molding.
The students had a budget with each sample having a cost. (For example, If they spent more on flooring then they most likely had to choose a cheaper paint or woodwork.)
The students really learned a lot about calculating area and perimeter and even about how to measure in the real world.