Best friends will love these mod cards they can see through. The vinyl is available at fabric stores such as Jo-Anns Stores, and a third of a yard (which makes about thirty 3-inch square valentines) will set you back only 2 bucks.
Place 2 layers of vinyl together and use regular scissors to cut a square or other shape from this double thickness. For variation, mix and match the top and bottom colors of vinyl
Peel the layers apart and lay one flat on your work surface. Place scraps of paper, including one with a message ("It's clear we're friends" on one side and "To" and "From" on the other), onto this piece and top it with the second piece of vinyl, pressing the edges together to create a sandwich. The vinyl pieces will stick together without glue. If you like, use pinking shears to cut a decorative edge or trim the square into a heart or other shape.