[Xaccers]

Bring back the tripartite school system but do it properly this time.
Academicaly minded kids go off to grammar schools, technically/vocationally minded (engineers, mechanics, electricians, plumbers etc) go to technical schools, and the rest go to secondary schools to get a decent education and life skills, with the allocation assessment not based on a single exam but a long term assessment so no one can be coached into an inappropriate selection, making it based on ability and potential ability rather than social background.
Fewer pupils at each school, smaller classes and better contact between teachers and pupils to get the educational support they need.
Of course you'd also need primary schools to actually educate pupils which may pose a problem.