Not many people even know how to weave anymore (at least in industrialized countries). We go to the store & buy ready-made clothes. Or, if we're ambitious, or just can't find clothes that fit, or want a special costume for something like Halloween or a Science Fiction convention, we might buy fabric.
Well, this month, I learned tablet weaving. Tablet weaving was used all over the world for thousands of years to make trim, belts, straps, ties, etc. You use some little cards with holes in them, usually 4 holes per card. One piece of thread goes through each hole, so if you have 4 holes, you have 4 piece of thread per card. Then you add cards until it's as wide as you want it. The piece I made used 7 cards and is about 3/8 inch wide. The math comes in how you thread different colors of thread through the holes, and how you turn the cards to make the pattern.
I just learned this, so I just copied the pattern given in the class handout, & don't really know how to explain how to use math to make other patterns, but I know it can be done. A Google image search for "tablet weaving" produces all sorts of fancy patterns.
Some good links to check out: