In physics the Heisenberg uncertanty principle is a well known limitation of measurements. The principle explains the fundamental conflict between establishing a particle's speed, and it's position. The more we focus on making one of these explicit, the more uncertain our understanding of the other. This is not a shortcomming of our instruments or anything like that, it is a fundamental property of the universe. Perhaps it is time that we realise that in education our ability to measure things like student attainment is even more limited. It is not a limitation that we can overcome by measuring more. In fact that just makes the situation worse, as our measurements then start to influence what we are trying to observe and ussualy not for the better. This effect is called the observer effect, and it is a crucial element to take inot consideration when delivering high stakes assesments.
With the increasing pressures on education to measure and report, calls to take into account the observer effect (although ussualy not referred to as such) are becomming louder. The National Union of Teachers conference has spoken out against the practice, and I have raised the issue on this blog before in the post titled High stake national assessments and ranking. A very thoughtful analysis of the problem is given by Wesley Fryer in his post Raising expectations. Wesley argues for the return of teachers designing and delivering high stakes tests, in stead of these being set by governments and awarding bodies. While a lot can be said in favor of this idea, I do think it is important to realise that this is only possible if we combine this with a very serious upgrade of the staff development that is given to our teaching staff on the subject of assessment. Nevertheless, Wesleys post is definetly worth a read. Especially this little gem:
"... bestowed upon the plebeian masses by the academic elites filling the hallowed halls of commercial companies now profiting handsomely from our myopic focus on summative, simplistic, high-stakes assessments". That must be the best and most colourful descriptions of our asessment culture that I have ever read.