Students create a survey with two choices, give that survey, answer questions about their data, and then create two advertisements using their survey data. (For example, cats versus dogs. The student would have to create an advertisement for both cats and dogs.)
I used this as a final project for my Math 7 class for the Rates, Ratios, and Proportions unit. I had a sub for two days, so kids did some work in class and I did provide materials such as construction paper, scissors, and coloring utensils for their advertisements.
The project discusses the ideas of unit rate, equivalent ratios, scaling up and down ratios, and comparing data.
My favorite part of the project was seeing how students manipulated their data to be misleading for one of the ads.