What happened when Boston allowed its best charter schools to set up new campuses?

standard-deviations-to-days-of-learning-for-mit-study

New MIT study says: The replication schools also provided superior performance.

One of the major contentions of charter school critics is that these schools of choice cannot be scaled up or replicated on a larger scale to include more students.

Well, new MIT research on the top-performing charter schools in Boston now undermines those notions.

The story began in 2010 when the number of charter schools in Boston was allowed to increase. As the MIT report puts it:

“Charter operators that the state deemed “proven providers” with track records of success were permitted to expand existing campuses or open new schools in these districts.”

As a consequence Boston’s charter school count rose from 16 to 32 between 2010 and 2014. The fraction of sixth graders attending Boston charters grew from 15 to 31 percent between 2010 and 2015.Boston’s charters are really popular, so the school system has to run lotteries to determine which students will actually go to a charter school. That provided the MIT research team with a randomized student sample set to evaluate: those who won a lottery position versus those who lost and had to attend a traditional Boston public school.

So, what happened?

The MIT report says:

“Lottery-based estimates reveal that Boston’s charter sector remained effective while doubling in size. Consistent with previous evidence, our results for cohorts applying before 2010 show that a year of attendance at a Boston charter middle school boosted math achievement by between 0.18 and 0.33 standard deviations…and increased English achievement by about 0.1 (standard deviations) during this period.”

Using a conversion found on Page 22 in a recent CREDO study that says each 0.01 of a standard deviation of extra learning equates to 7 days of extra learning, here is how those MIT findings look in more familiar days of learning format.

The obvious extra performance found in Boston’s charter schools is dramatic.

The MIT study continues:

“Results indicate that policymakers selected more effective schools for expansion: proven providers produced larger effects than other charter schools before the reform. Proven providers and other existing charters maintained their effectiveness after the charter expansion.”

Summing up, the MIT report says:

• Policymakers can reliably identify more effective charters.

• Replicating those top performing charters can be very effectively accomplished.

• The new, replication charters perform very well.

• Meanwhile, the parent schools in the replication don’t have to suffer any reduction in their effectiveness, either.

Bottom line: well-run charter programs are not only a win for students, but they can be successfully expanded. Real experience in Boston proves that.