In Dianne’s response below, she talks about two important assumptions we’ve made in ES’s recent report on interdistrict choice–one assumption about driving distance and the other about school capacity. Richard Kahlenberg, an ES Senior Fellow and a well-known advocate of using interdistrict choice as a means to achieve economic integration also takes issue with the assumptions we made regarding these two variables, saying that we’ve artificially limited the outcomes by choosing a driving distance and a school capacity estimate that are too modest.
I disagree with Kahlenberg that the assumptions made in the report are somehow irresponsible, but I do agree that they’re debatable and indicate areas where, as Dianne points out, additional research would substantially further the discussion on the feasibility of interdistrict choice. (Click here to see a full explanation of our assumptions and their impact on the report’s results—also available on page 4 of the report in a full-page sidebar, in smaller, but not fine print).
First up, the driving time assumption. We calculated the potential of interdistrict choice based on the availability of higher performing schools located within a 20-minute driving radius of each lower performing school. It’s important to note that the actual travel time is likely longer because the estimate doesn’t account for traffic or for picking up students along a bus route.
But, even so, is a 20-minute driving time unreasonably short? It might be if you’re a parent desperate for a better school option and willing to transport your kids up to an hour on the bus, but for many parents, most of whom like the idea of their children attending a school that is nearby and easily accessible to them during the day, a 20-minute drive would simply be reasonable. And if interdistrict choice is going to work on a large scale, it needs to work with reasonable commuting distances to schools – distances that allow parents to volunteer, attend PTA meetings, and pick their kids up when needed.
Even if we did assume that parents and students would be willing to commit to longer commutes, our results wouldn’t change by much. This is because, under our model, if one student can travel an hour, then all students can travel an hour. Therefore, increasing the driving distance both increases the available school choices and the competition for those choices. The limits of choice aren’t so much about 20-minutes versus 60-minutes, they’re about how many good schools are out there, how many students are competing to get in, and how much capacity higher performing schools have to enroll students from lower performing schools.
Which brings me to the second assumption – school capacity. Dianne makes the good point that school capacity is a “moving target”. It’s difficult to determine the actual ability of higher performing schools to expand—there is little available data and capacity might change from year-to-year along with population shifts and budgets. The recommendation made by the Aspen Commission on No Child Left Behind to require districts to audit available space in schools would go a long way to removing some of the mystery around school capacity and may, as Dianne predicts, reveal much more space than we’ve assumed is available.
But in the absence of that data, we still needed to make an assumption about the ability of schools to expand to take in transferring students—and we assumed that schools could increase capacity by 10 percent. If we made no assumption about school capacity and instead threw our hands in the air in bewilderment, we would have ignored a hugely important variable in the interdistrict choice equation. By settling on one number as a starting point for discussion, we’ve been able to move the conversation about interdistrict choice to a place it needed to go—talking about the practical limits and realistic potential of interdistrict choice.
In the end, what I hope readers take away from this report, and what I found particularly interesting, isn’t just the bottom line numbers or debate about our assumptions, but the fact that the potential of interdistrict choice can vary greatly from one community to the next—in some areas, it can have a much bigger impact than the overall numbers might indicate. In East Palo Alto, CA, for example, 35 percent of students could transfer with interdistrict choice–compared with only 9 percent in Los Angeles schools.
And it is this implementation of interdistrict choice programs that is crucial –where will interdistrict programs be most effective and how can they be implemented to best serve the students who are most in need of access to better schools.