A bunch of old pairs of jeans
Some quilt batting
About 4.5 yards of flannel for the back and binding
Step 1: Acquire a bunch of junky pairs of jeans. You can stock up on your own when they wear out, or you can pick some up at garage sales. We did a combo, we used some of our own and we picked up a couple at a rummage sale for $0.10 each. Cut off the hems and tops so you're left with these flat pieces (you'll get four flat pieces from each pair).
Then pin your layers together. Go ahead and do a quick basting stitch all the way around your quilt with a 1/4" seam to hold everything together. At this point, you may want to sew the layers together in the middle as well. You could could stitch in the ditch around the jean squares, or you could pick several places and just tack it down by repeatedly doing a forward stitch than a back stitch until it's secure.
Sew your strips together and iron your seam. If you're a fancy quilter you're probably not happy with my straight seam here. Quilters sew their binding strips together with a 45 degree angle, but I didn't want to, so if you want yours to look fancier, there's a good tutorial here.
Iron your strips in half with the rights sides facing out.
When you come to a corner, stop 1/4" away from the end, backstitch, and pull off the machine.
Pull the strip back so it is perpendicular
and then fold it over on itself so that it lines up perfectly with the edge of the quilt again. Pin in place and then begin sewing again on the new edge 1/4" away from the edge.
Step 7: Keep sewing around the quilt until you get close to where you started. Stop sewing about 8" from where you started sewing. Trim your loose binding ends so that when they lay on top of each other they have about 1/4" of overlap.
Fold them wrong sides together, pin, and then sew in place.
Finger press the seam open and test fit it. If the binding is too big and floppy, sew a bigger seam, if it's too tight, undo it and take a smaller seam. Once it fits right, sew the rest of it down.
Continue around the whole quilt, folding the corners neatly over themselves like so.
You're all done, now go out and picnic!
Just for fun, here are some other "interesting" denim things you could make!