“Educational Growth” and the Iowa Tests of Educational Development

Abstract

The Manual for the Iowa Tests of Educational Development (ITED) suggests that student “growth” of two standard score points per year is a good rule of thumb to use in interpreting change scores on ITED. This article argues that this rule can be misleading, and shows that, in fact, the amount of change to be expected from one year to another is quite variable, and depends upon the particular sub‐test in question, the grade levels under consideration, and the achievement level at which the scores happen to fall. Graphs are presented that show the amount of standard score change from grade to grade for each test on the national norms at the median and at the 25th and 75th percentiles.