I’m assuming you looked it up on greatschools.org, which is a good website... but not the best. It just so happens to be the first website that pops up when you google that question, but shouldn’t always go with the first website. It may be the most popular just not the most credible. You can be four years old about to turn five within the next five months. So my daughter, whose birthday is in November, could begin Kindergarten at 4 due to that discrepancy. As teachers we always recommend your child to have gone through Pre-K, IF they are to start at 4 years and 7 months.