That sounds like a good estimate for the cost of your kids. Our son's private school is about $1,900 a year or more like $2.5k with uniform, books, etc. Elementary is a great time for your for you kids to learn Spanish. Initially, our son was reluctant to study outside the U.S., but he's liking it more and more every day.
BTW, some of those cost on the spreadsheet included costs incurred while getting our resident visas, so they're extra high. We'd never spend $3k in one month here living the way we do. Ed