I missed the original message somehow. Was the title the same? A small refinement I use for the previous suggestion is to fold the square in half, cut out the shape open tbe square and the resulting pieces will be symmetrical. This is more simple for beginners because they don't have to be concerned about flipping. The fold line becomes a guide for taping in the correct location. As the students master this they can drop the folding step. Tessellation is not easy to explain without the visual!!!Good job, Marsha!!!