It would be unwise to roll out a program that isn't ready. But it is fair to ask why the Charleston County School District still is not ready to roll out its new evaluation system for teachers on schedule.

The Charleston County School Board in 2010 directed the administration to devise a system for evaluating teachers to include student performance on standardized tests.

In 2012 the district was awarded a $23.7 million five-year federal grant to develop and start a new evaluation system with value-added measurement (VAM) as a component.

Several states, including Tennessee, Ohio and Pennsylvania, began including student progress in teacher evaluations years ago.

And an evaluation system using student growth as a component is being tested in some schools in the district.

A handful of South Carolina schools already use a value-added method to assess and reward teachers. The 2008-09 value-added results for those schools were positive, with 95 percent of schools meeting achievement growth targets.

Is the concept controversial? You bet it is. Charleston County School District Superintendent Nancy McGinley Monday met with 19 passionate advocates and detractors of the evaluation plan under consideration, and said the meeting was fruitful. That's good. The more insights the district gets, the better.

Is it complicated? Of course.

But don't be surprised if the public views the district as dragging its heels, unenthusiastic about moving forward with a plan that is sure to bring criticism.

Much of the negative response is coming from teachers. In an op-ed in last Friday's newspaper, third grade teacher Patrick Hayes, director of EdFirstSC, an advocacy group, voiced strong objections to the plan, called BRIDGE, and cited research that indicates VAM systems "mis-classify teacher effectiveness 36 percent of the time."

But other research comes to different conclusions. A 2010 study by the Brown Center on Education Policy at Brookings concluded that "ignoring value-added typically lowers the reliability of personnel decisions about teachers."

Early on in the debate over using student achievement to evaluate teachers, opponents correctly pointed out that basing a teacher's performance on that one item would be misleading and unfair.

The plan the district is considering uses student growth as one of three factors. The others are classroom observations and teacher evaluations on a state system.

And student scores are measured in context through a specially designed, complex equation to neutralize factors like socioeconomic differences.

CCSD has asked the U.S. Department of Education to allow a one-year delay in implementation of its BRIDGE evaluation. It would begin in the 2016-17 school year.

The delay is based on three things: A new state test will be administered in 2014-15; at least one lawmaker has filed a bill about teacher evaluation; and the state hasn't completed its new teacher evaluation plan.

Unfortunately, there will never be a perfect time to roll out a new evaluation system. Education is a science that changes regularly, and politics is fickle.

And students need the best teaching they can get now, not later. Instead of delaying, it's time to look for solutions.