In Ohio: Lake Erie and if time permits Walleye fishing. The Ohio Island are a nice Ferry day trip and the Perry Monument is a must.
Canton has Pro Football Hall of Fame.
Columbus has OSU and Woody's Cathedral if you lime football. Hocking Hills in SE Central Ohio is a beautiful place. Old man's cave a good hike.
Give me some idea what your interests are. I traveled Ohio for many years. If you have children Cedar Point and Kings Island are good bets. KI has coaster fame and Cedar Point is on Lake Erie both are great amusement parks.