Even as a casual observer, it is easy to see the broad problem is bad parenting and awful students. Sure, there will always be people in the bottom 10% of any profession; some teachers may need to be removed. My assertion is parents have more control over their child's education. It is their responsibility to ensure their kids are putting in the requisite time studying and preparing. It is every child's responsibility to at least strive to improve themselves.
You cannot legislate or litigate success in life for people who do not accept any responsibility to themselves.
Also, I have my suspicions this could also lead to more damage to unions. Unions -- on occasion -- can benefit society.