If you are trying to come up with a relaxing weekend afternoon date, a trip to a local park may be an excellent time for virtually no money. If you have time, pack a picnic lunch to enjoy the full afternoon.
What your local park has will determine what you can do. If nothing else, there should be nice grassy areas where you can sit back and relax. If you want to get a little exercise, take along a Frisbee, ball and glove or football to toss around. Even if you don't play, there will probably be plenty of others that will be playing and you can sit back and watch them.
If the park happens to have a small pond, bring along some dried bread or make a stop at a bakery on the way for leftover crusts to feed to the ducks and other birds.
You can also bring along a kite to fly in the wind or some paper so that you can make paper airplanes and fly them around. Whatever activity you chose, the laid back atmosphere will make for a relaxing time and enjoyable date at little cost.