In prepping for the optional exercise portion of the class I see that you are asked to cut up a bunch of 1" squares of "solidish" fabric. Please don't feel that you need to spend a lot of time on this. Yes, paint chips would work fine if you have the time to get them, but I think crayons or colored pencils would work well also and would have the added benefit that you could color with them in your notebook to remind you of your discoveries. Anything else that you can think of that is small, easily transportable and comes in a variety of colors would work in a pinch: spools of thread? embroidery floss? Use your imagination and don't let cutting up tons of little squares of fabric stop you!