I've been wondering how I was going to do the flags for my Arabs. I'm not a huge fan of paper ones, so decided to have a go at making some plastic ones. Nearly everything else in the army is plastic so it makes sense to have plastic flags, too. If you want to make these at home you will have to ask an adult to help you.
I cut out 30mm squares of 1mm plastic sheeting. In order for them to keep their shape, they need to be heated, and any thinner than 1mm and it will be difficult not to over-heat them. I stick them in the oven at about 160C for a little bit. You need to keep an eye on them the whole time, and take them out and bend them a little as soon as they start to look warm. If you leave them too long they will just curl up and die.
Bending them just a little bit and then putting them back in the oven for a few moments seems to work well. And it takes about 4 or 5 iterations to get a nice clear shape. Be careful to make sure one of the edges of the flag is still very straight, so you will get a decent contact when gluing them to the pole. When they feel about right, put them in some cold water and they should keep their shape.
The original plan was to paint a load of fake Arabic writing on the flags, but not sure I want to risk that, atm. Might have to work up the courage for that.