re: Need way points for trip to Ohio

www.childrensmuseums.org will have a list. You can check any cities you know you will or would like to hit. Also check out the Reciprocal Network.
www.astc.org They have a list of their membership and details of the reciprocal benefits each offers.
Some places refer to themselves as children's museums but are affiliated with ASTC. Some science museums accept children's museums memberships. Sometimes a facility with accept either. We live in Mississippi and belong to the natural science museum in Jackson, which last year was $65 for our family of 7. We went to McWane Science Center in Birmingham, a phenomenal place fun for kids and adults alike, at no charge.
On occasion we haven't planned ahead and just used our GPS to tell us what was coming up along the way. We stopped in Shreveport on our way back from riding the Polar Express in Texas about six years ago and enjoyed an impromptu stop at that science center.