Teacher A's students just took one of many standardized tests. On this particular test 70% of his class is at goal or above. The 3 other standardized tests this class took show approximately the same percentage. Teacher B's students took the exact same standardized tests with quite different results. Teacher B's class has between 25% to 45% of the class performing at or above goal.
By looking at the achievement occurring in these classrooms, one could assume that Teacher A is a better teacher than Teacher B. He puts in long hours to help his students achieve great academic lengths. Teacher A is employing progressive, alternative teaching strategies. Each of these things very well may be true, but there is plenty that Teacher A's & B's scores are NOT saying. Teacher A's 70% were at / above goal BEFORE entering his classroom. Teacher A's students come from middle & upper - middle class families. Teacher A has less than 10% of his students receiving Free & Reduced Lunch.
Can we trust data? Is it an accurate picture of our students' abilities? Can we evaluate teachers based on their students' test scores? Should Teacher B seek advice from Teacher A because his students are higher achievers? Are we so blinded by numbers that we can't see the students, the human beings that inhabit our classrooms everyday?