I don't mind my tax dollars being spent on any children to be educated despite their parents. But I don't need to be hassled by the school about a family vacation either.... Really 2 separate issues. What happens where I live is there are limited spaces available for public pre-school. Students with an IEP who could benefit from pre-school are bumped to the end of the list because non-English speaking children are given higher priority for those limited pre-school student admissions (not IEP services). The priority levels are not secret -- poor children #1, non-English speaking #2, children with IEP #3 (if any room left). To make sure my son got the pre-school services that would help him, he went to a private preschool at a huge cost (and a 2nd mortgage). Well worth it too. Unfortunately, the teaching that goes on in his kindergarten class is well below his ability. Time for another 2nd mortgage......
It seems your point was limited to preschool then. I could make the same "argument" as you then. I have always had to pay. Why?? Because my children don't have an IEP and I do not meet the income guidelines. My son goes to a Public Integrated preschool as a peer model. I have to pay tuition and he cannot take the bus, even though the IEP students can. Guess what? I'm all for it. I thank God that I do not meet the financial guidelines for free preschool and my child does not have an IEP. I agree with offering free preschool to those that need it most. Preschool is not a requirement around here, and I don't think K is either (even though it is provided and free). Most preschools are tuition based around here. The very few public preschool programs are either for the very needy (financial or IEP) or for those that were chosen as peer models. I might be crazy but I think all children deserve a public education.
Just as the rules for teachers are not the same between districts, neither are the rules for students. My nephews school all vacations are unexcused but he gets 10 unexcused days a year. Sick days are excused (with a dr's note). I think the OP probably got what she needed. Her district requires an educational letter and she was looking for ways to word a letter.
OP - if you have not completed the letter yet; what subjects does your child take? That can help us give better suggestions if they are still needed.