While in Paris I bought some plastic coated cloth (toile enduite en francais) because the fishes on it were fun.
I have quickly made use of it by sewing a zip and making these cases, including the biggest pencil case that my daughter, number one, wanted to do with my help.
I've had to go twice to the haberdashery shop and bought nearly all their white zips in the sizes I wanted. It is a small shop, but very valuable.
I have since made 2 more, it's easy and fun.