Here are a number of graphs and tables for the last four years of test-taking by 8th graders in regular DC public schools and the charter schools.

This is the other grade where pass rates are generally going up, especially in math, in both types of schools. This makes me wonder whether (as suggested by Michelle Rhee’s fawning admirer and biographer, Richard Whitmire) the changing difficulty level of the test is the major cause.

Another reader of this blog suggests that perhaps math teachers have figured out which small fraction of the curriculum that is covered by the test, and have therefore decided to teach only that small portion — making the results look better, but cheating the students out of a fuller learning experience.

I don’t know, but would love to hear from those with some knowledge.

One thing is for sure: in the 7th and 8th grade, charter school students are scoring higher than those in the regular public schools. My suspicion is that many, many concerned and involved — or simply wealthier –parents of middle-school students fear what they perceive as chaos and poor behavior at the regular public schools, and they pull their students out of regular DC public schools at that level, and transfer them to alternatives: private or charter schools. So the students ‘left behind’ in a lot of our regular DC public middle schools (not all, of course, but a significant fraction) are the ones with parents who aren’t involved, for whatever reason.

The graphs are in the usual order.

Math pass rates are going up pretty steadily in the 8th grade among regular DCPS students. A straight line regression indicates ‘pass’ rates reaching the NCLB-required level of 100% by 2022. In reading, the pass rate still is below that of three years ago; a straight line regression says that in reading, the magical 100% pass rate would be reached by 2045. Both predictions are, of course, nonsense.

As you can see if you compare the two previous graphs, ‘pass’ rates for black DCPS 8th grade students are about 5 percentage points below those for all DCPS students. Straight-line extrapolation still predicts 100% pass rates by the years 2022 and 2045, respectively. But don’t repeat that with a straight face. (grin)

As you can see, ‘pass’ rates at the charter schools in the 8th grade are significantly higher than in the regular public schools. I’ve indicated why I think that is happening. If you do a straight-line regression, 100% ‘pass’ rates will be hit around 2017 or so. Of course, the regression also indicates that 200% of all students will pass the test in a few more decades. And if you believe that, then you will also believe in the Tooth Fairy, Santa Claus, and the pot of gold at the end of the rainbow.

Again, significant rises in pass rates among black 8th grade charter school students.

If you compare this with similar data for the elementary grades, you will see that the proportion of black students in the public schools at the 8th grade level is considerably higher, which validates my suspicions about opting-out by more well-to-do, or more-involved parents and their children.