The first chart below provides overall national ranks of achievement in four areas: pre-school tests (the National Assessment of Educational Progress), high school completion, preparation for college and adult educational attainment. Across all four of these categories Kansas is tied for 8th in the nation. So we should start by pointing out that under our state’s current charter school law, Kansas has higher performance than 80% of the other states, including many with more liberal charter school policies.
However, states vary significantly in the student populations they have to educate. The next chart shows the percent of low income students (those eligible for free or reduced lunch) for each state, as well as the percent of majority (white) students. There is a very high correlation (0.83) between a high educational achievement rank and a lower percentage of low income students. That means the more low income students in a state, the lower that state’s achievement tends to be.
If you aren’t familiar with statistical correlation, remember that 1.0 is the highest possible correlation; it essentially means a “one to one” correspondence between two variables. For example, New Hampshire has the lowest percent of free/reduced eligible students in the nation and ranks second in achievement; Mississippi has the highest low income population and the lowest achievement. Note also that ethnicity, although significant, has a considerably weaker correlation with achievement rank than income (0.49). That is not really surprising: economically advantaged minority students usually perform as well as majority students from similar income levels, and low income white students struggle academically.
I have also highlighted the 10 states closest to Kansas in percentage of low income students. Only two rank in the top 25 on achievement; Illinois at 20th and Indiana at 23rd. Note that Arizona, which has a slightly lower percent of low income students than Kansas, ranks 26th in low income students but 43rd in achievement.
Note there is an almost insignificant 0.2 positive correlation between the percent of students in charter schools and achievement rank, and an even more insignificant negative correlation with a high charter school law ranking. In other words, charter schools make almost no statistical difference in state achievement. Also, there is no statistical correlations between the percent of students in charter schools and the percent eligible for free lunch. This means charter enrollment is not disproportionately grouped in higher or lower income states.
Each of the ten states with a low income student percentage closest to Kansas (in pink) had a higher percentage of students in charter school. Yet Kansas ranked higher than every state with similar low income enrollment except Indiana – which spent more per pupil and had slightly fewer low income students.
There is an insignificant, but negative, correlation between charter school enrollment and NAEP scores, which essentially means that having more students in charter schools makes no difference in fourth and eighth grade reading and math. Note that Michigan and Arizona, two of the highest charter school enrollment states, are both similar to Kansas for low income students, but score in the bottom 10 states.
NAEP tests only provide achievement data up to grade eight. The next chart ranks states by an average of four different graduation rates from national reports. As with NAEP scores, Kansas ranks 11th in the nation. Of higher ranking states, six had fewer charter school students than Kansas. Kansas had higher achievement than every other similar states based on low income students, although every other similar state had higher charter school enrollment.
The table also shows that some states with high NAEP scores fare much worse in actually graduating students. For example, Indiana ranks 7th in NAEP scores, but falls to 23rd in graduation; Colorado drops from 13th on NAEP to 29th in graduation, and Florida drops from 20th in NAEP to 42nd in graduation. Note that there is 0.29 negative correlation between the percent of students in charter school and the average completion rate.
The next chart shows the states where most students take the ACT test for college, including Kansas. We use a formula to adjust the percent of students who meet college ready benchmarks in reading and math by the percent of students tested and the graduation rate. Kansas ranks 9th, which would be an adjusted rank of 17th if applied to all 50 states. Five of the eight higher-performing states had more students in charter schools, but every higher achieving state spent more per pupil.
Again, there is a modest negative correlation between charter school enrollment and the percent of students meeting college-ready benchmarks, which means states with more students in charter schools are somewhat less likely to have higher achievement. Note that Florida ranks third from the bottom, and Arizona, the state with a higher percentage of students in charter schools, ranked last. On the other hand, some high achieving states like Minnesota, Utah and Colorado have a high percentage of students in charter schools, but also have a much lower percentage of low income students.
This data is very clear. First, Kansas is already a high achieving state, despite having more low income students than most states. Second, statistically having more students in charter schools makes no difference in achievement, and in some cases has a modest negative correlation. Third, Kansas already does better in achievement in almost every case than similar states, regardless of charter school enrollment.
What the data shows is that states with fewer low income students tend to have higher achievement, regardless of charter school enrollment. On the other hand, high charter school enrollment doesn’t help states with higher poverty do better. In other words, charter schools haven’t solved the 911 emergency of student achievement.
What does help boost achievement? We also provide the total revenue per pupil for each state. In every case, total revenue per pupil has a statistically stronger correlation with achievement than charter school enrollment.
Let’s be clear: we can’t be satisfied with Kansas outcomes. We need to be truthful about the number of Kansas students who are not achieving at satisfactory levels. But we also need to be truthful about the equal or greater achievement problems in high charter school states. Expanding charter schools has not proven to be the answer.