Do you have a link for that "equally well" part? My understanding is that all have to meet certain minimum standards.
The Letter from the federal dept of education to the state schools has:
Under the NCLBA, schools are held accountable for the achievement of all students, not just average student performance. Ensuring that schools are held accountable for all students' meeting State standards represents the core of the bipartisan Act's goal of ensuring that no child is left behind.In a nutshell, the requirement is that the "subgroups" MUST reach minimal standards. There is no mandate to try to have non-"subgroup" kids do better than "proficient". Therefore, all available resources will be channel toward meeting the mandate (minority kids meeting minimum standards) at the expense of non-subgroup kids who have the potential to achieve better than just "proficient"...
However, any Title I school in which any group of students fails to meet the AYP goal must be identified as in need of improvement, and all such schools that are identified are subject to the timeline for improvement required under Section 1116.
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A State's definition of AYP is based on expectations for growth in student achievement that is continuous and substantial, such that all students are proficient in reading and math no later than 2013-2014
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States must set separate, measurable annual objectives for each of these subgroups that ensure they meet the deadline to reach proficiency within 12 years.
Subgroups for accountability are major ethnic/racial groups, economically disadvantaged students, limited English proficient (LEP) students, and students with disabilities. The goals for each subgroup may be the same as long as each subgroup reaches 100 percent proficiency in 12 years.