I wouldn't give those people another dime until they started performing.
The place to start is with parents.
Give them vouchers and hold their feet to the fire.
The scenario makes sense: Dad gets called away from work because Johnny is not in school. Dad has to chase down Johnny and return him to school or he will lose the voucher and Johnny will instead go dig ditches.
At the end of each school year, Dad gets the test reports and then is held to account by the state. If improvement is not shown, then the voucher is withdrawn and given to a more deserving child.
100% parental responsibility. It would work!