Almost every town has a park, common, beach, or a common area where residents can gather (if yours does not, visit surrounding towns and discover theirs).
The first three games in this list are definitely outside entertainments. The remaining two can also be enjoyed inside, should the weather take a turn for the worst.
You may already have most of the items needed for these games. If not, consider taking one day to visit some yard sales in advance, looking for kites, frisbees, paper suitable for origami, bubble wands, and marbles.
1. Fly a kite in your local park. First, make your own kite!
2. Play frisbee golf at your local park. (You will of course need at least one frisbee). Either mark off (using ribbon tied around trees) your course, or make a map. Count the number of throws it takes for you to hit the next “hole.” Person with the lowest score wins. Be sure to clean up when your game is done. Note: this sport, also called Disc Golf, has gone professional, DOH!
3. Blow bubbles. Have a bubble blowing contest (i.e. largest bubble, bubble that drifts the furthest etc. Make your own bubble tube and bubble formula first.
4. Create origami. Take leftover paper, wrapping paper, or construction paper outside on your deck, or picnic table (obviously on a day that is not too breezy). Use some of the diagrams for creating origami on the internet, and some for paperfolding. There are even web sites dedicated to kid's origami.
5. Play marbles. Most of us have some of these hanging around, but we never learned to play. You can either draw the rings on the ground, OR you can use chalk to draw the needed circles on pavement. Learn how to play here, and here, and here.
If you know of other almost free things to do (for all ages) please share. And most of all, have fun!
PS: Also see -Four Strangely Amusing New Hampshire Entertainments-