I would venture over to your son's school and ask them. Or, you might be able to search for your son's school online, and then glean the information from their website. If the website does not include the information, I'd call them directly and ask them.
Hi, Congratulations on this special milestone in your son's education!
You can use SchoolFinder to research your local schools and school district: http://www.education.com/schoolfinder District pages are hyperlinked from the individual school pages. To get the best search results, enter your city, state and zip code in the search bar.
School assignments vary by school district so contact the district to learn which school(s) your son may attend. I also suggest asking about kindergarten orientation or a PTA contact who can connect you with other kindergarten parents at the school. When our daughter started kindergarten, attending the orientation and Back to School PTA meeting really helped us to meet other members of the school community, learn about the school, and feel welcome.
Below are some additional resources you may find helpful. I also suggest bringing along some pocket tissue on the first day of school (should thoughts of your baby 'growing up' cross your mind)! Congrats again!