Couple days ago the Wallstreet Journal had an article written by Mr. Marc Bernstein, a former New York state superintendent of schools, stating that in New York state teacher evaluations showed 95% of teachers were “highly effective” or “effective,” 4% as “developing,” and only 1% as “ineffective” for the 2012-13 school year.  It then addressed a simple common sense question as to why over 50% of all 4th through 8th graders weren’t proficient in reading and math, according to statewide test scores.  No, it isn’t because all those 1 and 4 per centers teach 4-8 grades.  It’s worse.
Read the article (it is behind their paywall so it may not show).