Leveller asked

And if an able and experienced educator concludes from a lifetime in the field that grades, standardised tests, lesson plans, set times for subjects etc. are precisely the problem.......
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I'm not clear what the relevance of this is. Are you saying that the answer to flaws in the education system is for everyone to educate their children at home...or simply pointing out that there are deficiencies, with which many people, teachers included, would probably agree?

No, Homeschooling isn't the answer for all, but if they exist they should not adopt the worst weaknesses of the state system...prescribed curriculum, testing, grading etc. The present system of testing in the UK is formalised child abuse ( kids really do show psychosomatic symptoms, anxiety, bed wetting etc) and kills curiosity.
   I have known some wonderful schools, both within and outside the state system, and my preference is for humaistic scholing. However, I have also known many who would have been better off not going to school at all, especially with formal instruction at four years old. The system can be improved, see the Finnish system, or the danish folk schools, etc.