Misleading information on charter schools

The National Alliance for Public Charter Schools released a statement challenging Hillary Clinton’s townhall statements about charters. I examined their statements and found them technically accurate but misleading. The first few make an apples to oranges comparison of all charters to all other public schools, even though the percentage of charters in urban locations (which have a higher percentage of English Language students) is twice that of all public schools. The other statements cherry pick data.


“There is no difference in the percentage of English Language Learner (ELL) students served between charter and non-charter public schools.”

Technically, this is correct. The percentage is slightly higher in charter schools, according to their source, 9.1% at traditional public and 9.8 at charters.  However, this is actually an apples and oranges issue. The same source says that city schools are 15.1% ELL students while rural schools are 4.8% (suburban are 8.6% and rural 4.8%). But Digest of Education Statistics Table 216.30 shows that over half of all charters are urban (56.7%) compared to only a quarter (25%) of noncharter public schools. Also just 10.8% of charters are rural compared to 29% of noncharters. So based on location, if charters were reflecting the ELL percentage of their community, we’d expect a higher percentage for charters. A more accurate comparison would compare the percentage of ELL students in charters and traditional public schools in the same district lines.

Also, the same source says that only 65.6% of charters have at least one ELL student compared to 74.3% of traditional public schools.


 “37% of charter schools have at least 75% of their students in poverty as compared to 23% of non-charter schools.”

Again, because the percentage of charters that are urban is twice that of noncharters, this comparison is misleading. According to the Department of Education’s Condition of Education report, in 2010, 38% of city schools have at least 75% of students eligible for free or reduced price lunch compared to 10% of rural schools. A better comparison would be poverty in the charter schools compared to poverty in the district.


“Nationally, in the 2013-14 school year, charter schools served a higher-percentage of low-income students (57%) – than district-run schools (52%) – and have better outcomes”

The first half is just a variant on the previous statement. Again, as poverty is not evenly distributed, a better comparison would be charter schools to noncharters in the same district.

Also the link provided as evidence of better outcomes was to a CREDO study that compared urban charter schools to other urban schools in the same community (precisely what I advocate above for their other measures).  Moreover, this report was for urban schools only. It does not prove better outcomes for the other half of charter schools. A different CREDO study looked at all charter locations in the participating states but this national study found only a slight advantage (the equivalent of eight extra days) for charters in reading and no difference in math.


“2015 NAEP scores show that in Los Angeles, there was dramatically better student performance in charter schools than with district-run schools. Proficiency rates were triple that of non-charter schools. Los Angeles charter schools demographics are 75% low-income students and 85% of student have minority status.”


This is a classic example of cherry picking the data. Los Angeles is just one of several districts on which NAEP provides information. But if they didn’t cherry pick, they couldn’t claim an advantage for charters. Overall, there was no statistical significance between in the difference between charter and noncharter NAEP scores for large cities.

I also compared charter/noncharter for national public overall. The only statistical significance was in fourth grade math where noncharter public students outscored charter students.


“In New York City, charter public schools do a better job of retaining students with disabilities than their non-charter public school counterparts. Specifically, 53% of charter school kindergarteners with disabilities were still in the same schools 4 years later, compared with 49% of non-charter schools.

This is accurate. It makes the right comparison, unlike the others above, comparing NYC’s charters to noncharters. Again, however, this is only one district and, as the report only looked at NYC schools, there is no way of knowing if this is true for other districts.


So, overall, this statement is completely truthful in what it says but highly misleading. Mathematically, because the percentage of urban schools among charters is twice that of non-charters, urban charters could serve a lower percentage of ELL and low-income students than their neighboring noncharter schools, and still have higher percentages compared to all public schools (in all locations).