You can use them as a substitute for batting. Just sandwich them like you would a batting.
Square up a piece about 6" longer than you actually want for a blanket. Cut a 3" square from each corner. Fold each edge in 1 1/2" and seam 1 1/4" from the folded edge. Make 1" cuts ever 1/2" all the way around your blanket. With your fingers or a large crochet hook start with one loop and pull the next one through it. Do this all the way around the blanket until you come to the last loop. Cut it through the middle or on either side, loop it through your first loop then hand stitch it back together. This will give you a fleece blanket with a beautiful "braided" looking edge. Kids seem to love them like this. You can do the same with smaller left over squares. When the stitching is done and the loops are cut, put two together and crochet one loop from one side with a loop from the other piece until you reach the fourth side. Put a pillow form in and finish the last side. Now you have a matching blanket and small pillow---absolutely wonderful for traveling. I almost forgot, when stitching down the edges use a bit of a zigzag or other stretchable stitch.