Charles M Achilles is considered a leading expert on class size and its impact on student achievement. As a primary investigator for the STAR (Student Teacher Achievement Ratio) study conducted in the State of Tennessee

Tennessee

Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...

, Dr. Achilles established the link between smaller class sizes and increased pupil performance. This study still influences educational leaders today and stands as one of the few truly quantitative, large-scale educational studies.

Currently a professor in the Seton Hall University

Seton Hall University

Seton Hall University is a private Roman Catholic university in South Orange, New Jersey, United States. Founded in 1856 by Archbishop James Roosevelt Bayley, Seton Hall is the oldest diocesan university in the United States. Seton Hall is also the oldest and largest Catholic university in the...

 Ed.D. program through the Seton Hall University College of Education and Human Services

Seton Hall University College of Education and Human Services

The College of Education and Human Services is a post-secondary degree-granting institution concentrating in education within Seton Hall University in South Orange, New Jersey...

, Dr. Achilles is also an expert on problem analysis and research design

Study design

Clinical study design is the formulation of trials and experiments in medical and epidemiological research, sometimes known as clinical trials. Many of the considerations here are shared under the more general topic of design of experiments but there can be others, in particular related to patient...

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