What is a bell curve, and how does it relate to school evaluations?
The normal distribution of scaled scores will form a bell curve. Specifically, if a group of students is given a standardized test, the standard scores will be distributed to form a bell curve. Fifty percent of the students will receive a standard score of 100 or less and 50% of the students will score above 100. Fifty percent of the students will fall in the average range, which on the bell curve is between 85 and 115. These students will be considered low average, average, or high average depending where they fall between 85 and 115. Two percent of the population will score 70 or below and 2% of the population will score 130 or above. The score of 130 is considered a superior or gifted score.
