Here's a quick and easy way to make treat bags out of things you probably have already. Directions are below.
Cut out a square from an average size plastic grocery bag. You should be able to get two squares per bag. Place some candy in the center. I recommend white candy so it doesn't show.
Cut off the top of the plastic bag. Turn over so the knot is at the bottom. The candy will fall to the bottom of the bag, (it serves as a weight). Draw on a face with black marker.