the average reading scores of students assigned to three highly effective teachers in a row rose from the 59th percentile in fourth grade to the 76th percentile by the end of sixth grade, and students of similar ability assigned to ineffective teachers for three consecutive years fell from the 60th percentile in fourth grade to the 42nd percentile by the end of sixth grade. (educationworld.com)
Yet by the end of sixth grade, none of those students are proficient in reading or math. (educationnext.org)
Children who do that consistently can wind up two years behind their classmates by the end of sixth grade. (gse.harvard.edu)