Summarize this article in one sentence.
You will need a large piece of duck cloth (you can generally purchase swaths of duck cloth that are 7 inches wide and 56 inches long.) You will also need scissors, a ruler, a sewing machine, fabric glue, a bag of feed corn, and a digital baking scale. You can also use a needle and thread if you do not have a sewing machine. Using your ruler, measure out 7 inches (17.8 cm) at a time to make sure you are accurate. You should make 8 of these squares. Using either a sewing machine or a needle and thread, sew 3 of the sides closed. Keep in mind that you should be sewing 1/2 an inch in from the edge of the squares. Only do this on the sides that you have sewn up. Even though you have sewed these sides, gluing the extra fabric together will make it less likely that your bean bags will leak. Again, flipping your bag inside out makes it less likely that your corn will leak out. Place the feed corn onto your digital baking scale and add or remove corn until it weighs 15.5 ounces. Then put the corn into the bag. If you do not have a digital baking scale, 2 cups of feed corn is very close to 15.5 ounces. It may not be exact but it will be close enough. Fold the 1⁄2 inch (1.3 cm) edges into the bag and hold closed. You can use a pin to hold the edges closed. Try to place your stitches as close to the edge as possible. Doing this will make the bag as evenly sized as possible.

Summary:
Gather your supplies. Cut the duck cloth into 7-inch by 7-inch squares. Match 2 of the squares up so that they are perfectly aligned. Put a line of fabric glue in between the edges of the two squares. Flip your bag inside out. Add 15.5 ounces of feed corn to each bag. Measure 1/2 an inch in on the side that is still open. Sew the final side shut.