my daughter's 6th grade class (maybe 5th?) was learning about tesselations so I coordinated the students who made foundation-pieced blocks, one apiece, that when put together was a tesselation. I used the school's colors of purple and white, mostly purples divided into light, medium, and dark. depending on the dark or light chosen, the medium went the other way. The kids had a blast, and the foundation piecing (which was done under my supervision and many of the kids had foundation-pieced schoolhouse blocks with me in the 3rd grade) helped the blocks hold up even to less-than-perfect stitching. It was great fun. If I'd remembered to take a pic, I could have shown it to you. The pattern was the snail trail with a 4-patch center.