Students will be constructing a foldable on the real number system (rationals and irrationals). The foldable has three layers: (1) Title, (2) Example, and (3) Definition. There are many options on how you can have students construct the foldable. You can provide students with the foldable already filled out with answers, or you can give them a blank template and have them fill out the foldable. Also, you can mix and match layers so that one layer already has answers and then the next layer needs to be filled out.