i made this for an article last year for the website i used to do crafts for.
patterned felt and solid *hard* felt. (they make some felt that is "harder" than regular, soft felt. i used the harder stuff for the background, but soft felt would work fine as well).
various patterned papers
valentine heart candy
printer or stamps or pen
plastic treat bags.
cut a felt background out of the hard felt, large enough to fit inside your treat bag. cut strips of a patterned felt to make a "bingo" board on the hard felt. attach with glue. insert enough candies that the kids can play "bingo" with their valentine candy. i used two different colors, so it wouldn't be confusing. insert directions for the game and make a cute topper for the treat bag.