I like this reply feature that sends an email to keep the conversation going. 
The welfare-economic argument for --any-- government role in the education industry depends on deficient parents. A universal age 5 or 6 through age 16 or 18  attendance law is like a law that compels all 5-18 year olds to stay in a hospital even if they are not sick.  "Public education" has become an employment program for dues-paying members of the HSTA/HGEA/UPW cartel. If this is not so, why cannot any student take, at any age, an exit exam (the GED or SAT will do) and apply the taxpayers' sub-18 education subsidy toward post-secondary tuition or toward a wage subsidy at any qualified private-sector employer?