Updated with an Additional Year of Data: Comparing Student Attrition Rates at Charter Schools and Nearby Traditional Public Schools

January 2015

Updated with an Additional Year of Data:
Comparing Student Attrition Rates at Charter Schools
And Nearby Traditional Public Schools

PDF version available here.

Summary

About this time last year, IBO issued a report that examined whether elementary grade students in charter schools leave their schools any more frequently than students in traditional public schools. To do this, we studied a cohort of more than 3,000 charter school students and 7,200 students at nearby traditional public schools who entered kindergarten in September 2008 and followed them through third grade. This new report tracks the same cohort for an additional year and extends our observations through the 2012-2013 school year, when most of them were in fourth grade.

Among our key findings:

On average, students at charter schools stay at their schools at a higher rate than students at nearby traditional public schools.
Students at charter schools left the city’s public school system at the same rate as students in nearby traditional public schools.
When we consider any student identified as having a disability in kindergarten as a special needs student, these students remained at their charter schools through the 2012-2013 school year at a higher rate than similar students at nearby traditional public schools.

To produce this timely update to last year’s report, we have focused on the major observations from the prior report. We have also used a broader definition of special needs students than we did in the previous report.

This schools brief uses an additional year of data to update IBO’s January 2014 report that measured and compared the rates at which elementary grade students in charter schools and students in nearby traditional public schools leave their schools. That report examined a cohort of students who entered kindergarten in September 2008 and followed them through the 2011-2012 school year. This involved tracking data on 3,043 students in 53 charter schools and 7,208 students in 116 traditional public schools nearest to each charter.

We compared the rate at which charter school students in this cohort left their kindergarten school with the rate at which those in the same cohort in neighboring traditional public elementary schools left their schools. We also compared the attrition rate for various sub-groups of students.

The availability of an additional year of data now allows us to report on these same students as of the 2012-2013 school year, when most of them were in fourth grade. We are also able to update our analysis of the attrition rate for students with special needs, using a broader definition of “special needs” than earlier New York City Department of Education (DOE) data files provided.¹

Incorporating the additional year of data, our main findings confirm those of our earlier report:

Using the broader definition of students with special needs, which is consistent with how the DOE typically reports on these students, yields results that are quite different from our previous findings regarding the relative attrition rates of students with special needs.

When we consider any student identified as having a disability in kindergarten as a special needs student, 53 percent of such students attending charter schools remained in the same school four years later. The corresponding rate among students flagged with a disability in nearby traditional public schools (again, restricting to those who had already been classified as having a disability in their kindergarten year) was 49 percent. As is true for all students, the gap is fully explained by the difference in the rates of transferring to another New York City public school.

The initial kindergarten class of the charter schools in our sample contained a smaller percentage of students with disabilities (8.9 percent) than that of the traditional public schools in the sample (12.7 percent.) Grouping these students by their type of disability, the distribution for students in charter schools looks similar to the one for students in nearby traditional public schools. The most common reported disability in either sector is “speech impairment.” Among charter school students with a disability in kindergarten, 70.0 percent were recorded as having a speech impairment; in nearby public schools, the corresponding figure was 68.5 percent.
In kindergarten, the charter schools served a lower percentage of students with learning disabilities (8.6 percent of students with disabilities) than public schools (11.2 percent) and a higher percentage of students with “other health impairments” (10.5 percent of students with disabilities compared with 8.6 percent.)

Among students who were classified as other health impaired, those in nearby traditional schools were more likely to remain in their same school than those who started in charter schools. But among students with other types of disability (speech, learning, and all other), it is those who started kindergarten in charter schools who stay at their schools at a higher rate.

Endnote
¹One charter school and one traditional public school included in our original report did not offer a fourth grade in 2012-2013. We drop the students attending these schools from the analysis in this brief, as the focus of this brief (as also the original report) is to look at mobility patterns as observed in nonterminal grades.

Students Attending Kindergarten in 2008-2009 School Status as of 2012-2013 (October, 2012)
Attrition Status	Students Starting Out in Charter Schools	Students Starting Out In Nearby Traditional Public schools
All Students
Number of Students in Grade K (September 2, 2008)	3,004	7,178
% in Same School in 2012-2013	64.2	55.6
% in Different NYC Public School in 2012-2013	23.1	31.6
% Who Left NYC Public Schools by 2012-2013	12.7	12.8
SOURCE: IBO analysis of Department of Education data New York City Independent Budget Office

Attrition Status of Students with Disability Students Attending Kindergarten in 2008-2009, School Status as of 2012-2013 (October, 2012)
Attrition Status in Various Years	Students Starting Out in Charter Schools	Students Starting Out In Nearby Traditional Public schools
Students with Disability
Number of Students in Grade K (September 2, 2008)	267	914
% in Same School in 2012-2013	52.8	49.1
% in Different NYC Public School in 2012-2013	34.1	39.7
% Who Left NYC Public Schools by 2012-2013	13.1	11.2
SOURCE: IBO analysis of Department of Education data New York City Independent Budget Office

Students with Disability in Charter Schools and Nearby Traditional Public Schools By Type of Disability Identified in Kindergarten, Students Attending Kindergarten in 2008-2009
Type of Disability Classification	Students Starting Out in Charter Schools		Students Starting Out in Nearby Traditional Public Schools
Type of Disability Classification	Number of Students	Share of Students With Disabilities (%)	Number of Students	Share of Students With Disabilities (%)
Speech Impaired	187	70.0	626	68.5
Learning Disabled	23	8.6	102	11.2
Other Health Impaired	28	10.5	79	8.6
All Other Disabilities	29	10.9	107	11.7
Total Number of Students	267	100.0	914	100.0
SOURCE: IBO analysis of Department of Education data NOTE: “All Other Disabilities” include the following categories of disabilities: autistic, emotionally disturbed, hard of hearing, intellectual disability, multiply handicapped, orthopedically impaired, preschool disability, and visually impaired. New York City Independent Budget Office

Attrition Status of Various Subgroups of Disability Students, Students with Disability Identified in Kindergarten School Status as of 2012-2013, (October, 2012)
Attrition Status in Various Years	Students Starting Out In Charter Schools	Students Starting Out In Nearby Traditional Public Schools
Type of Disability Classification
Learning Disabled
Number of Students in Grade K (September 2, 2008)	23	102
% in Same School in 2012-2013	52.2	47.1
% in Different NYC Public School in 2012-2013	39.1	41.2
% Who Left NYC Public Schools by 2012-2013	8.7	11.8
Other Health Impairment
Number of Students in Grade K (September 2, 2008)	28	79
% in Same School in 2012-2013	53.6	58.2
% in Different NYC Public School in 2012-2013	28.6	29.1
% Who Left NYC Public Schools by 2012-2013	17.9	12.7
Speech Impaired
Number of Students in Grade K (September 2, 2008)	187	626
% in Same School in 2012-2013	54.5	50.6
% in Different NYC Public School in 2012-2013	33.2	39.6
% Who Left NYC Public Schools by 2012-2013	12.3	9.7
All Other Disabilities
Number of Students in Grade K (September 2, 2008)	29	107
% in Same School in 2012-2013	41.4	35.5
% in Different NYC Public School in 2012-2013	41.4	46.7
% Who Left NYC Public Schools by 2012-2013	17.2	17.8
SOURCE: IBO analysis of Department of Education data New York City Independent Budget Office