“School hours in the United States were developed during the 19th century, in part to allow students to help their families with farm work in the afternoon,” writes Peter Orszag. “We are no longer an agrarian economy, but most schools still get out around 3 p.m.” It’s time for a change:

A longer school day, especially if combined with other steps such as frequent feedback to teachers from administrators and intensive tutoring, could improve academic achievement. For example, Roland Fryer and Will Dobbie of Harvard University have found that a longer day is a key aspect of high-performing charter schools in New York. Fryer found similar results for traditional middle and high schools in Houston: Implementing reforms there, including a longer school day, produced large gains in math performance (albeit modest to no gains in reading). More time at task improves student achievement.

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