One of the (many) education reform proposals that has received national attention over the past few years is “extended learning time” – that is, expanding the day and/or year to give students more time in school.

Although how schools use the time they have with students, of course, is not necessarily more or less important than how much time they have with those students, the proposal to expand the school day/year may have merit, particularly for schools and districts serving larger proportions of students who need to catch up. I have noticed that one of the motivations for the extended time push is the (correct) observation that the charter school models that have proven effective (at least by the standard of test score gains) utilize extended time.

On the one hand, this is a good example of what many (including myself) have long advocated – that the handful of successful charter school models can potentially provide a great deal of guidance for all schools, regardless of their governance structure. On the other hand, it is also important to bear in mind that many of the high-profile charter chains that receive national attention don’t just expand their school years by a few days or even a few weeks, as has been proposed in several states. In many cases, they extend it by months.

Although KIPP is among the more extreme examples, many KIPP schools add 3-4 hours to the day and a few weeks to the year (e.g., via mandatory Saturdays and/or summer school). Although these comparisons vary by location, when you compare the total number of hours to that of schools in their host districts, KIPP schools offer between 40-55 percent more time. This is a rather striking discrepancy, which can represent the equivalent of 3-4 additional months of schooling using the typical 6-7 hour regular public school day (regular public schools couldn’t fit all that time into the calendar without lengthening their days). This may be one of the primary reasons why at least some KIPP schools spend more money than comparable schools in their areas.

And, again, it’s not just KIPP – the majority of high-profile operators use expansions -- often large expansions -- of the school day/year. Sometimes, this extended time is evident across charter sectors. In 2008, for instance, the New York City charter school sector as a whole offered an average of 30 percent more school time than the city’s regular public schools.

I have argued that these massive extensions of the school day and year may be one of the big concrete policy characteristics that explain the success of high-profile charter models. Although, to reiterate, time must be used wisely, it’s not hard to argue that adding the equivalent of 2-4 months to the school calendar might serve to boost student outcomes of various types. And the empirical evidence, though still thin, tends to support this viewpoint.

Therefore, regular public school districts certainly should consider expansion of the school day/year as a viable option to increase student performance. However, to whatever degree they are basing this on the results of the few high-flying charter school chains, they would well-advised to bear in mind the sheer scope of extension at these schools, and to adjust their expectations as to possible results accordingly.

- Matt Di Carlo