Charter schools, test scores, and assumptions
I pulled myself out of the stupor I was in as I collapsed on the couch this afternoon just long enough to hear a news report about how some new study "showed" that students at charter schools scored worse on tests than students at regular public schools. I'm sorry that I'm so vague about the particulars, but the last few days have been a BEAR.
Now, I am rather neutral on the whole charter chool issue in general-- although the ones that have opened around here have been cited for sloppy record-keeping and shady financial deals, not to mention unqualified teachers. But that may not be the case everywhere. I can easily imagine that they COULD be done well-- unfortunately, I just haven't seen it.
So once again, this got me thinking about studies and statistics. First, do people not really understand that most "studies" in this country are hardly performed by disinterested third parties? Rather, many studies are created by interest groups as propaganda, and the statisticians compiling them are far less interested in ascertaining the "truth" than in gaining ammunition to support their particular point of view-- or at least the point of view of the people
Second, there are several variables for which it seems this study did not control. Consider: in many places, students whose parents place them in charter schools are fleeing chaotic former schools. A successful student is probably not going to prompt a parent to uproot their child. But a struggling student would be most likely to provoke a parent into taking a chance on an alternative school setting. Hence. how do we know that the students at charter schools didn't enter these school already behind in skills and test scores?
It's like comparing public school students to students at chi-chi private schools. Private schools can and do limit which students they accept, whereas public schools must take all comers. But control for income and other factors, and a different story emerges.
The study gets reported because it's news. People accept the story because it's on TV. But that doesn't prove the claims to be true.