A parent’s plea on teaching

Michael Laser, via a kind reader’s email:

IF I could change public education, here’s what I’d do first: reward the best teachers with higher pay and stature, and fire the worst teachers, because they shouldn’t be in the classroom.
My children have gone through a total of 16 years of public schooling in New Jersey. Over the years, I’ve seen outstanding teachers, and outstandingly bad ones. Our kids have had teachers who introduced them to everything under the sun, and made every day different and fascinating. Some of our daughter’s teachers gave up their lunch and stayed late to help her find her way through the maze of math. Two of our son’s teachers comforted him when traumatic events laid him low. My daughter’s sixth-grade teacher made students feel like real scientists; her language arts teacher covered everyone’s papers with useful suggestions. These people put everything they have into teaching. They light sparks that stay lit for years.
But we’ve also seen teachers who put dents in our children’s spirits, day after day, teachers who barely taught anything at all, who, I suspect, chose the profession because they wanted summers off.
My father used to come home from his post office job railing about co-workers who didn’t do their share of the work, but couldn’t be fired. Watching bad teachers fail to do their jobs, I’m even angrier than he was. How can anyone justify protecting the jobs of teachers who: