I have made it known that I am no fan of using value-added measures in teacher evaluations. There's just too much room for error, and there's too many things that can go wrong, from the test to the calculations. Value-added calculations are done in a mysterious black-box and there is too little oversight and protection measures in place to ensure that the data is error-free. As the Washington Post reports here in "Errors Found in D.C. Teacher Evaluations," more than 40 teachers received incorrect teacher evaluations of the year 2012-2013. One teacher was even fired due to miscalculations. That is totally unaccepted and should not every happen.
Many states, including my own, have adopted the "Value-added measure fad" without piloting or studying it at all, other than listening to the sales pitches and lobbying of companies peddling this methodology. In North Carolina, there is currently no recourse for challenging the scores either. If a teacher suspects their ratings are incorrect, there is no way to independently validate it. But if your goal is to implement corporate reforms measures, any mis-calculations and faulty teacher ratings are acceptable, as long as we implement the reform measure. According to an additional post on the Washington Post Web site, "D.C. Schools Gave 44 Teachers Mistaken Job Evaluations," it was faulty calculations "of the value that D.C. teachers added to student achievement in the last school year resulted in erroneous performance evaluations for 44 teachers, including one who was fired because of a low rating."
This incident illustrates clearly that value-added measures used in teacher evaluations are too error-prone and should be discarded. When education policy gets too caught up in numbers and statistics, people, whether teachers or students don't matter as much to the number-crunchers. The Obama administration should be ashamed of mandating this mistaken education policy too states to begin with. States who have implemented these measures need to immediately discard this statistical fad because it will ultimately do more to harm education than help. North Carolina needs to drop this fad too and begin moving their educational system into the 21st century. Sadly, our state leaders are so blinded by the numbers they just can't let go.