As you will see from the pictured bag we have used a different fabric (pink) for our recess to the lining (blue) and then a patterned outer and also for the zipper tabs.
Pupils will need to bring a 1/4 metre of fabric for the outer and another 1/4 metre for the lining. Plus a small amount of contrast fabric if you wish to make your recess from it. If you want to use the same fabric as your main fabric or lining this is fine. (The pattern pieces you will need to cut from it are 2 x 9.5″ by 3.5″ rectangles so a scrap will suffice). You will also need an 18″ zipper with nylon/plastic teeth.