Is UFT President Mulgrew right to assert that charter schools in New York City perform better only because they are “selective” in admissions. To Mulgrew and other charter critics, “selective” refers to the open-to-all lotteries required of charters. Apply, and you have a shot at getting in. But the more motivated parents are the ones who apply, say the unions. That’s a legitimate point, although in researching my book in San Jose I found nearly as many parents who applied to Rocketship schools because of the longer schools hours (free child care) as applied for academic reasons.
Regardless, that selection bias has to be considered. On the surface, the kids may look the same — same race, ethnicity and income levels — but they are not really the same. Some come from families with more motivated parents. Selection bias can be disproved. Studies comparing students who got into good charters via a lottery to those who didn’t get in show that the charter education, not the selection bias, is what makes the difference. There are many studies showing the true academic gains found at the good charters.
In the end, however, just plain common sense prevails. Those gains you see from, for example, the KIPP studies are too big to be explained away by selection bias.
In truth, there may be more selection bias found on Mulgrew’s side, among the traditional public schools. Best summary of that comes from the “No Velvet Ropes” analysis done by the New York City Charter School Center. Mulgrew’s sector is chock full of selection bias — starting with the school attended by the mayor’s son. Here’s an op-ed summarizing the report, but frankly the op-ed is not as powerful as the actual report: 32 percent of all the traditional middle and high schools in the city exercise some form of selection. That makes New York charters look like the pinnacle of equal opportunity.