Product Description:
This study addresses three questions:
First, considering the full group of students and the special education subgroup, what is the likely effect of minimum cell size and confidence interval size on school-level AYP determinations?
Second, what effects do the changing minimum cell sizes have on inclusion of special education students, especially for schools that are declared as "meeting AYP"?
Third, with the NCLB requirement that schools assess grade levels 3?8 in their AYP calculations beginning in the 2005?2006 academic year, what is the likely effect of including these additional students in school-level AYP determinations?
To address these questions, data from five states were used to model confidence interval and cell-size combinations.
Increases in minimum cell sizes for the special education subgroup were associated with a large increase in the number of schools meeting AYP targets for each of the five states assessed. Increased confidence interval sizes were also associated with an increase in pass rates, but a much smaller increase. While raising the minimum-n is an effective means of increasing the passing rates of schools, it does so at a considerable cost to special education students in terms of being excluded from the accountability system. When the data were modeled to reflect testing in all grades 3?8, many more special education students? results are included in the accountability system, assuming that states will not increase the minimum-n. If the implicit theory of action guiding NCLB accountability requirements is to improve instruction and thus outcomes for all students, schools and districts must be accountable for all subgroups in order to ensure that these students are appropriately served. The effect of increasing the minimum-n to exclude substantial portions of special education students must be considered a threat to the validity of the accountability system.
