I generally stay at the state parks and the closest for you would be Alum creek state park. It is not a far drive off the 71 and they recently upgraded the park and now have a bunch of full hookup sites, but book early LOL. They have a beach there and a separate camping beach as well and a marina where I also think you can rent out boats.
Almost directly across the street from that is Cross Creek campground and it does have a pool but like a typical private campground is the sites are tight with no separation in between them, and also they are more expensive.
The zoo from there is like a 15 minute drive and is great. As another poster stated, the zoo is connected to Zoombezi Bay water park. Not far from Alum creek is Skyzone trampoline park which the kids might like, also a 10 minute drive from there.
The zoo is north of the city and Cosi is in downtown Cbus so you could hop back on the 71 and take it right into the city.
If you need any other info just let me know. Hope it helps you out and have a good time!
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