Here's an example of what to say and how to reach out:
I understand that it is possible for Agricultural Science classes to count for substitution of required and elective science classes in special circumstances determined at the local school district level. I would like to determine if my son's/daughter's [Ag. science course name] taught by [Ag. science course instructor] could possibly count towards high school science graduation and college admissions requirements. My [son/daughter/myself] [insert name] really enjoys the hands-on learning of these classes. Please consider approving the [agriculture course name] for science credit and visit www.IowaSTEM.gov/AgisSTEM to learn more about the pathways for approval.
One example model Agricultural Science curriculum well-established in Iowa that satisfies Iowa Core Standards in science subjects is CASE (Curriculum for Agricultural Science Education). Here's their flyer for more information: CASE Flyer