At the school level, the teachers doing a bad job in the classroom are not a mystery to their peers or to a good principal. And while a bill backed by Gov. John Bel Edwards will tweak the way teachers in public schools are evaluated, the measure breezing through the Legislature does not change the fundamentals of teacher evaluations.

Senate Bill 342 is the product of lengthy negotiations among teachers unions, superintendents, the Louisiana School Boards Association and advocates of major changes in public schools, including the Louisiana Association of Business and Industry, the Council for a Better Louisiana and Stand For Children.

These are groups of widely varying views, and some of them pushed strongly under former Gov. Bobby Jindal for teacher evaluations based on 50 percent of a principal’s classroom observations and 50 percent on growth of student achievement, measured by test scores under a controversial “value-added” model.

What hath negotiation wrought?

The growth in student achievement will be 35 percent of the teacher’s score, not 50 percent. The difference will be made up of other measures.

Underwhelming as this shift is, the fundamentals of the 2010 law that kicked off the new system appear to be in place.

Principals still will be required to make classroom evaluations, and schools will continue to be evaluated by their performance scores.

We like the fact that there is some objective yardstick of performance in the system, but 35 percent or 50 percent or even more is not the overriding consideration. Rather, it is that there will be a focus on teacher quality in the classroom.

Today, the value-added model applies to roughly 20,000 of Louisiana’s 50,000 classroom teachers where student test data is easily available, such as math and science teachers. Other teachers are assessed on student learning targets, which are academic goals for students agreed on at the start of the school year by teachers and principals.

All those factors — including test scores, which are key parts of a school’s performance score — continue to make the regular evaluation of each teacher part of the routine in every public school. Principals and superintendents must be focused on this big-picture rating, because scores will suffer if they allow poor teachers to continue in the classroom without intervention.

A good principal, and teacher peers, know whose classrooms dissolve into chaos and whose students are showing poor attitude and poor academic performance. Whether the test data is at 35 percent or some other number does not strike us as a revolutionary change.

Given the original and bitter battles over evaluations, among all the groups involved in the new bill, SB342 might be studied in Sunday school, not public school, as an example of the parable of the lions laying down with the lambs.