This is a case-by-case decision that can only be made by the parent(s). For example, how many years are left in their K-12 education vs how many years are left on the tax roll? This research must be done before any decision can be made. That sometimes means a long road ahead of contacting tax assessors and reaching out to many other local and state tax authorities. If the child has 10 years left in their education but there are 12 years left on the tax roll, then it can be paid off while the children is kept in the public education system. If less, lawfully one should remain enrolled. The tax roll can be thought of as a yearly subscription plan to certain public services. The subscription can be paid in whole for longer periods of time than a year, essentially until the date the tax roll renews.
NOTE: Should the public school system and/or district's board of education discover through an in-depth property tax assessment report that a specific property does not pay property taxes, and it is the location of a student who attends classes in their district, they lawfully have a right to refuse service and then charge on a per-use basis. The chances of this occurring are astronomical. The fee would be in the range of $400 to $1,500 a month for educational services, depending on the district.