My daughter's birthday is on Valentine's Day, so we always try to work that into her party theme. This past year, we had a heart shaped pinata, filled with Valentine straws, cards, candy, and small toys.  The kids loved it.  Before they opened the pinata, I had given them each a small red, pink, or white bag, and they got to decorate them with Valentine stickers, stamps, and washable markers.  It was a poject that they loved and at the same time it gavr them some down time to relax.  The cake was also shaped as a heart, and I surrounded it with small, Valentine decorated cupcakes.  Her baloons, plates, napkins, and silverware were all Valentine colors also. It made a really nice party, and the kids enjoyed the theme. I thought next year it might be nice to have them each bring in a small box and have them decorate them to hold their pinata goodies.