Jacqueline Edelberg: Great Teaching: Not Just a Good Idea, It's the Law (Almost): ...So, if a great teacher produces great results, what does an ineffective teacher produce? Turns out, it's a pretty shoddy product. A recent study by Eric Hanushek, the Hanna Senior Fellow at Stanford's Hoover Institute featured in Waiting for 'Superman,' proves that an above-average teacher produces a year and a half's worth of normal test score gains in a single academic year, while a below-average teacher raises their students' scores by only a half a year. Consequently, unlucky children saddled with poor teachers fall further and further behind.
In a city like Chicago, which suffers from a colossal achievement gap (only 6 percent of CPS high school freshmen will graduate from college), the disparity might seem insurmountable. Not so, says Hanushek. A great teacher can bring even the lowest performing students up to grade level in just three years. If great teachers, or even merely average teachers, replaced their lowest performing counterparts, Hanushek predicts the nationwide economic impact due to increased test scores and higher future earnings would amount to $100 trillion, roughly the same number of clams required to wipe out the entire national debt.
