Have you used post-it notes for a creative math lesson yet?! (See my post from 2012 about post-it math art). They're a fantastic tool to introduce the concept of area and reinforce perimeter. For this lesson, students used 25 or less post-it notes. We made a prediction: Do different shapes that have the same area have the same perimeter? Working in groups of 4, students mapped out their design on 1-inch graph paper and figured out the area and perimeter of their shape. Then, they found a blank wall to construct it! Click here for more math/art projects!