Welcome!! I agree with others that zip lock bags would work great, easy to label as well. Good idea to have students help organize. Glad to know you have saved some of each fabric you have purchased, will make a great quilt. Remember when you have your blocks organized and start to store them make sure you keep them out of the direct sunlight in the room you store them, because sun will cause them to fade over time, keep them in a dark area of the room if possible. Please share photos of your cushions or whatever you make. T help sew a straight line, you can u a piece of tape and line it up on the right side of the needle on your machine for the width of the seam you are sewing as a guide, so the seam edge of your fabric runs along the edge of the tape. I hope this makes sense.