20. On the first windy day of spring go buy the $4 kids kites from the grocery store and fly them in the park.
21. If you live somewhere without light pollution, sit outside and try to identify as many constellations as you can. There’s some handy apps for this, or you can just try from memory and be creative.
22. Build a fort and then make out inside it.
23. Join a rec league and play on the same team together.
24. Find a coffeehouse that has live music and go there for a night. Even if you have two drinks each coffee is inexpensive and you’ll have paid less than $10 each for a whole night’s activity.