Go on a search for as many good climbing trees as possible, climb as high as you both can in all of them, compile photo evidence.
Go to a major chain bookstore, and leave notes to future readers in copies of your favorite books.
Create photo evidence suggesting that you went on an adventure that didn’t really happen.
Adjust the lights to a low setting and build a fort out of furniture and blankets.
Try and visit as many people as you can in one night, and change as many things around inside their apartment without them noticing.
Go to the airport, get the cheapest, soonest departing flight to anywhere and stay there for the weekend.
Rent a season (or two of your favorite show) and watch them all marathon style with a big bowl of popcorn.
Go for a walk, and collect various things you find along the way. Later, see who makes the most creative design from their found materials.
Write a piece of fiction together. Outside a cafe. Ask strangers when you get stuck.
Go downtown with a video camera and interview strangers. Pretend it’s for a film workshop.
Dress to the nines, pretend to be married, and go out for a fancy dinner.
Do the lamest tourist thing in your area that you both secretly think would be fun.
Volunteer at a local animal shelter for the afternoon.
Blindfold one, and let the other feed him/her foods of their choice. Try to guess them then switch.
Go to a public library/book store and take turns reading your favorite childhood stories to each other.
Get into your pajamas, prepare some hot chocolate and/or snacks and go to the latest showing of a movie. It’ll feel like sneaking out when it’s past your curfew.
In the middle of the night, drive to the beach, so you arrive just before the sun rises. Have a breakfast picnic.
Drive somewhere unknown and have dinner in a city you’ve never been to. With fake names and/or fake accents.
Pick a challenging recipe and attempt to master it together.
Go around the city with sidewalk chalk and draw hearts with equations on random things.
Rent a movie you’ve never seen before. Set to mute, and improvise the dialogue.
