I've used rag quilts (made of flannel) for camping and while sitting on the side lines for sporting events. They go together quickly, and assuming you've washed and dried them sufficiently, they'll be done shedding by summer time. I've washed and dried them at home. Make sure if you do this too, that you stop your dryer every 5 minutes to clean out the lint trap. No, I'm not kidding. Set a timer and clean it out that often the first bunch of times you dry it. Rag quilts shed like crazy, but if you wash and dry it a bunch of times, then most of the shedding will be in your washer/dryer. Good luck.
If you get the flannel from JoAnn's, then you can use coupons. Keep in mind there are cheaper flannels and then there's quilter's flannel. You get what you pay for. I've used both for rag quilts. All depends on what your budget is. If you decide to make a rag quilt, feel free to drop me a line and let me know how that worked out for you.