Mary C. Tillotson, via a kind reader:

California’s laws surrounding teacher tenure, dismissal, and layoffs violate the state’s constitution — specifically, students’ right to an equal opportunity to access quality education — say nine students suing the state. The trial is set to begin Jan. 27.
If they win, the effects could ripple across the country.
“I think any time that you see a genuine reform in California, you empower reformers everywhere in the country who realize if you can actually fix something like that in California, you can fix it anywhere,” said Ed Ring, executive director of the California Public Policy Center.
Plaintiffs argue that minority and poor students are most in need of effective teachers and least likely, in California, to be taught by them.
“Research has shown that inside the school building, nothing matters more than the quality of the teachers,” said Sandi Jacobs, vice president for National Council on Teacher Quality. “An effective teacher and a highly effective teacher make a really significant difference in the trajectory of their students, and the same is true in the negative capacity for an ineffective teacher.”
Other factors, like parents’ level of education, are also correlated with student performance, but as far as factors schools can control, teacher quality matters more than any other variable, she said.