Here is another look at the brand-new data concerning four variables in the District of Columbia schools, about which I wrote a couple of days ago. The difference here is that the dots representing the schools are more-or=less proportional to the size of the student body.
1. Is this a regular public school, or a charter school (blue or red):
2. What fraction of the kids at that school are officially considered to be At Risk? (That’s the scale along the x-axis at the bottom of the page)
3. What is the average percentage of the kids at that school are ‘proficient’ in reading and math on the DC-CAS? (That’s the scale along the y-axis at the left-hand side of the page)
4. How big is the school? (That’s the size of the dot, more or less; the legend is at the bottom left-hand corner of the graph)
Time spent looking carefully at this graph will be well-spent. If you click on it, it will expand.
It will certainly show that charter schools have not revolutionized education for the better in DC: for both types of schools, there remains a very strong, negative correlation between the percentages of kids At Risk and ‘pass’ rates on the DC-CAS.
Note that most schools have between 200 and 500 students and that most of the ones that are smaller are actually charter schools. As I wrote a couple of days ago, the schools with the largest fraction of At-Risk students (say, over 2/3 of the student body) are almost all regular DC public schools.
On the second graph, which is otherwise identical to the first, I’ve labeled some of the larger schools.
Here is the one with names of some of the larger schools, so you can see how individual schools fall on this graph.
(Sorry, I there was not enough room to label every single one, and my non-existent HTML skills won’t allow me to make it so that any of the dots are clickable. If any of my readers know how to do that and would like to offer to make that happen, then please let me know in the comments.)
And here is the entire data table. So you can see where every single school lies on these three dimensions.
(PS: I added a few more names of schools and corrected four other small errors, two pointed out by an alert reader.. 2/22/2015)