According to a new study of graduation rates in large cities, only 58.2% of Austin's high school students earn a diploma.
AISD reassures us the real number is over 77% -- the study "doesn't adjust for things like students moving into private schools, students moving out of state and students entering home-schooling. The data our state prepares are much more precise because they are actually tracking a student over time."
I dunno. Just eyeballing AISD's own enrollment data (pdf), the study seems plausible:
12th grade classes have only 80% or so of the enrollment of the 10th grade classes two years before. And that's enrolled 12th graders. I imagine well under 90% of enrolled seniors graduate each year.
The pertinent question anyway is how many 9th graders graduate. 9th grade attrition is probably much higher than 10th grade because weaker students are retained in the 9th grade (note the persistent bulge in 9th grade enrollment).
I'd be surprised if much more than half of the students who start the 9th grade end up graduating from AISD.
This is a small sample, of course; perhaps these figures are just anomalies. And, yes, this is a crude, seat-of-the-pants analysis. But if 77% of all high school students graduate, you'd expect that to be reflected in relative class sizes.
As for AISD's explanation for the drop in class sizes: Sure, some of these students move away. But some students also move into town. I suspect that families who move to the suburbs for the schools tend to do so before their kids hit the 10th or 11th grade. I also have trouble believing that there is a large exodus from public to private school in the middle high school years (although I'm sure it happens).
This study blames low graduation rates -- and the alleged under-reporting of graduation rates -- on high-stakes testing. I realize that graduation rates are ideologically fraught statistics. But the theory makes sense to me: High-stakes testing (and No Child Left Behind) incentivizes principals and administrators to demonstrate yearly academic improvement. Since they (and probably teachers, too) have little real control over student improvement, their natural incentive is to run off the bad students and jigger the graduation rates to disguise what's really going on.
(Of course, this incentive exists for all schools, not just AISD, and I know that the state has elaborate rules for reporting drop outs -- I'm not accusing anyone of fraud, perhaps just creative accounting.)
Perhaps AISD should consider incentivizing those who can actually make a difference. I don't have a problem with paying students to study -- we subsidize college education; why not high school? There are large, positive spillover effects from education, which means people typically underinvest in their own education. This is a classic market failure that can be fixed (perhaps) by the government setting the proper incentives.