Go to a drive-in movie
South Drive-in, South Side
Sure, you could venture into an indoor theater for a break from the heat, but movies from the back of a pick-up truck, the late summer evening breeze in your hair and a date by your side, are way more rad.
Pro-tip: If you go to South Drive-in, don't turn around and look at the other screen (SPOILERS!). Also, the flea market there is worth checking out if you're into that sort of thing.
Hit up "The Beach"
At Alum Creek
Any time I took a friend last year to my favorite "secret" spot in Columbus, they were shocked to discover this sandy treasure. The water's always cool and clear, the sand fine and clean and there are plenty of grills for a little barbecuing. So pack a picnic, lay down a towel and spend a lazy Sunday afternoon with me on the banks of Columbus' best beach.
Pro-tip: Want something a little more fast-paced? You can rent boats of various speeds at Alum Creek, too.
Read books in a hammock
At various Columbus parks
Or maybe just nap. Yea, that sounds pretty great too.
Pro-tip: If you're the cheap sort, you can make a hammock by tying large knots in the ends of a king-size sheet and wrapping a looped rope around each knot before tying off to a tree. It works better than you think.
Explore Columbus via water
At Columbus rivers and lakes
I grew up a river rat. That happens when your hometown exists at the confluence of the mighty Ohio and Muskingum rivers. My summers were spent in boats, diving off docks and swinging out over riverbanks from rope swings. None of those things have happened since moving to Columbus two years ago. I aim to return to my river roots this summer via canoe or kayak.
Pro-tip: Get in those waterways now before everyone else does when the restored Scioto and Olentangy rivers project is completed in 2015. Then you can be a hipster river rat and say you were into the rivers before they were cool.
Build a raised-bed garden and grow food
At my backyard
Few cliches get my mouth watering more than the one that says food grown by your hand tastes more delicious than food bought at the store. I don't even like raw tomatoes, but sweet Jesus the ones I grew two summers ago were amaze-balls. And the abundance! I had banana peppers spilling out my ears and zucchini and squash for miles. I didn't care that every meal that summer included these foods, because, yup, they were that good.
Pro-tip: My wife and I took part in a community garden when we started and loved the communal aspect of it. Or, more truthfully, we loved flooding our garden neighbors with our newbie questions. Similarly, that might be a good option if you've never had a garden before.