Interest Factoids on Value-Add

Last night, I attended a meeting of the Colonial Hills PTA where the subject of "Value-Add" came up. Value-Add is a metric that measures student growth - whether the student, grade, school or district achieved a years worth of academic growth for a years worth of time. Being the left brain type that I am, I wanted to understand in detail the algorithm that was used to determine this. Much to my surprise, the algorithm is not published and is not available, not even as a public record. I've been told that the algorithm is enormously complex and that disclosing it would not demystify it. In any event, I came across an interesting article on the efforts by the State of Ohio to smooth out the rough spots on the value-add calculation and make it a more reliable indicator. As you go through the article, make sure you click on the value-add primer and on Doug Clay's article on the yo-yo effect. The article is here:

http://www.educationgadfly.net/flypaper/2011/08/from-ski-slope-to-a-bell-curve-ohio%e2%80%99s-evolving-value-added-measure/