I separate my scraps into three piles when I get around to sorting them children, women, and men. Then when I decide to make a scrappy quilt I go to the designated box and make a quilt! This works best for me. I have a go to quilt pattern called "Magic Square" and it works well for this method. Since I only make quilts for girls, I haven't had to make a boy or girl pile as of yet.
Happy quilting!