Flag Material - help!

[igz00.livejournal.com]

The boyfriend and I are pretty heavily involved in scouting and his scout troop needs to make patrol flags. (The troop is broken up into patrols of about 8 kids and each patrol is represented by color or animal or whatever the kids want.) Details here: http://www.troop142bsa.org/sketchbook/Patrol%20Flag%20.pdf

The flags will be exposed to the weather on camping trips once a month, and used every week at troop meetings. The idea is that the kids will design their own flags using the materials we provide for them.

Example:


So I'm looking for a type of fabric that is durable enough to last through about a year or more of Michigan weather (rain, snow, sun, etc) and 11 - 18 year old kids playing with it every week. I am also looking for a way to draw on said fabric that will not bleed or run if wet (so markers are out.)

I was thinking Nylon or Polyester and fabric paint. Am I on the right track? What would you recommend?