(Doing calendar calculation.... You're talking about entering him at age 4.3?) Check the state law for early entrance on the ODE website. I recall that it's virtually impossible in public schools to do early entrance if the child's birthday is after Dec 31. I do not recall if a district is allowed to be more flexible.

Also consider skipping K and starting 1st at age 5.3.

Either way, districts in OH are supposed to use the Iowa Acceleration Scale for early entrance K or skipping a grade, so you will need IQ and achievement before opening the discussion with the district.