By Dr. Marciene Mattleman

PHILADELPHIA (CBS) – Philadelphia is cited in articles about the national trend in declining school populations and its effects. Detroit and Cleveland are in similar situations. In the last four years, Los Angeles dismissed more than 8500 teachers and other workers as enrollment fell by 56,000.

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Large declining districts are left increasingly with children with disabilities, poverty and the need for learning English. In Cleveland, where enrollment fell by one fifth, special education services increased by 23%.

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Because school financing is usually allocated on a per-pupil basis, plummeting enrollment can affect curriculum and require fewer teachers. Before the Mesa Unified District in Arizona closed four middle schools, it lost teachers in music, art and technology.

Randi Weingarten, president of the American Federation of Teachers notes that such trends cause greater stratification and segregation.

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Read more at NYTimes.com.