I’ve done some more number-crunching using DC-CAS data. This time, I followed individual cohorts of students as they passed through DCPS from 2008 through 2011, looking to see if there was any truth to the many boasts of educational Deformers like Rhee and Henderson.
Even I was surprised at how little progress there was.
I added up the percentages of black students, and of white students, who are deemed “proficient” or “advanced” in math and reading at the various grade levels for each of the years 2008 through 2011. Then I made tables and graphs showing how these DC-CAS ‘pass’ rates changed as I followed a cohort, or age group, of students through these years.
For example, in the first graph and table, I have the 3rd grade scores for 2008; followed by the 4th grade scores for 2009; followed by the 5th grade scores for 2010; and finally, the 6th grade scores for 2011. On the whole, those are the very same students (except for those who transfer in or out of DCPS, or who are retained in grade or skipped ahead). It’s the closest I can do to what Educational Deformers call “Value Added Measurements”.
On the whole, it is clear that the enormous gap in ‘pass’ rates in both math and reading between white students and black students has essentially not changed a bit, despite Michelle Rhee’s many claims of success. Rhee has also said in The Bee Eater that she expected principals to be able to raise their pass rates from 20% to 70% in just a few years. Did she succeed? I say no way, but look for yourself.
I will first look at the cases where we have data for all four years, and then look at the cases where only 2 or 3 years were testing years. (You probably remember that the DC-CAS is only given in grades 3, 4, 5, 6, 7, 8 and 10.)
First: The Cohort that Finished 6th grade in 2011:
Second: the cohort that finished grade 7 in 2011:
The cohort that ended grade 8 in 2011:
(recall that grade 9 is not tested under DC-CAS or NCLB, so we only have data for this cohort for grades 6, 7, and 8)
Next, the cohort that ended grade 10 in 2011:
(again, there is no data for 2010 for this group, when they were in the 9th grade)
I’ve mentioned before that I think that 10th grade scores are unreliable, because of the tricks that high school administrators perform in choosing who is held back in the 9th grade until they are too old to go on to the 10th grade, and are skipped over into the 11th grade, or else encouraged to drop out.
Next, the cohort that finished grade 4 in 2011:
(we only have two years of scores for them)
The claims of Michelle Rhee and other educational Deformers have been put to the test. In the DC public schools, the test scores did NOT rise as they claimed, and the black-white gap stayed quite stubbornly in the range from 45 to 55 percentage points.
Thus, even by her own standards, she is a failure.