While this score is a favorite among non-educators, it is one of the most misunderstood measures of student achievement. It is often viewed as an absolute measure of whether a student is performing at some absolute standard of "grade level". It is, just as often, misunderstood to indicate that a student is capable of doing work well beyond his/her grade level. That is, if a fourth grade student achieves a grade equivalent score of 10.4, or tenth grade fourth month, then educators are often asked why the student has not been moved forward to a higher grade.

What the grade equivalent score actually measures is how typical students at the grade level specified would perform on the test that has been given. In other words, the grade equivalent of 10.4 does not indicate that the 4th grade is doing of doing 10^th grade work. Rather, it indicates that the 4^th grade student has performed as well as a typical 10^th grade student would have performed on the 4^th grade test. If the student is performing on grade level, that is a 4^th grade student taking the test in the 10^th month of 4^th grade receives a score of 4.10, then it simply indicates that he/she is performing right at the average for other 4^th graders in the norming sample, which is the 50^th percentile and 50^th NCE.

Grade equivalents do not lend themselves to measuring aggregate performance of all students in a school or school district. They do not average well and are hard to understand when dealing with groups. Accordingly, the score used in this study is the Normal Curve Equivalent, or NCE.