Chapter 1: Explanation of the Data and Sample

The data gathered for this story were obtained from the Civil Rights Data Collection (CRDC), a series of datasets that contain information on key education and civil rights issues in U.S. public schools. The CRDC is publicly accessible through the Department of Education’s Office of Civil Rights (https://civilrightsdata.ed.gov/data/). The CRDC data set contains information on student enrollment and educational programs and services, as well as on disciplinary practices such as suspension and expulsion. Beginning in 2010, the CRDC has been conducted every other year, with the latest available pre-pandemic data (2017-18) released in October of 2020. In the data story presented, we examined the use of exclusionary discipline (ExD; total out-of-school suspensions and total expulsions for students with and without disabilities) reported in the last three pre-pandemic CRDC data sets, 2013-2014, 2015-2016 and 2017-2018). The CRDC data for the 2020-2021 (data collection was delayed a year due to COVID-19) were released in November of 2023 and are not included in this data story.

One of our goals of this data story was to present information on patterns and trends in the use of ExD over time. As such, we only included schools in the 50 U.S. states and the District of Columbia that reported ExD information for all three of the data collections used. Additionally, we did not include any schools that were identified as pre-kindergarten, alternative, magnet, correction/detention, single sex, online, or special education schools. Finally, we only included schools that fit the definition provided by the Department of Education (see National Center for Education Statistics, 2022) as either elementary, middle, or high schools. Elementary schools were defined as schools that offer more of grades kindergarten through fourth grade than higher grades. Middle schools were defined as school that offer more of grades 5 through 8 than higher or lower grades. High schools were defined as schools that offered more of grades 9 through 12 than lower grades. Thus, we did not include schools that combined middle and high schools into a single school, nor did we include schools that enrolled students in all grades from kindergarten to 12th grade. Finally, some schools failed to report either their enrollment or use of ExD and were not included. Thus, the final sample used in this Data Story totalled 78,626 schools (47,270 elementary; 14,910 middle; 16,466 high schools) enrolling more than 45 million students in each of the CRDC data collections.

Because we have a large sample of schools the reported data over the three data collection times, we could examine questions related to patterns of change in the use/non-use of ExD over time. Specifically, some schools changed from one year to the next in whether or not they suspended/expelled students. In contrast, other schools were consistent in their use/non-use of ExD over time. Thus, we could make some comparisons among schools that changed in the use of ExD and examine outcomes associated with these changes.

Based on the data for each school in each of the three data collections, one of the ways we examined our research questions was to assign every school to either a Use Group (U) or a Non-Use Group (N) for each data collection. If a school reported zero cases of suspension/expulsion, it was classified as "N" for that year. If a school reported at least one case of suspension/expulsion, it was classified as "U" for that year. Based on the pattern of use across the three data collections, each school was assigned to one of seven Use/No Use classifications. These included two classifications where schools either used or did not use ExD across all three data collections (U/U/U or N/N/N) and six in which the schools changed in Use/Non-Used during at least one of the data collections (N/N/U, N/U/N, N/U/U, U/N/N, U/N/U and U/U/N).

Most of the tables and graphics presented in this story were created using Tableau and are interactive. Users can actively scroll through the data, sort. and select the information desired, and get more detailed information by hovering the cursor over individual cells or data points. We hope that users find this interesting and informative as we highlight what we believe are the key findings and discussion points. 

We present most of the findings from our data analyses as descriptive graphics that portray and highlight the trends and patterns. We do this primarily for readability purposes. Because of the large sample size, most of the differences discussed are statistically significant. Readers are encouraged to contract the authors for the results of these analyses.

As noted, we do not include the CRDC 2020-2021 data but plan to do so over time. Thus, the data presented in the story to date reflect patterns prior to the COVID-19 pandemic and the impacts that school closures had on ExD and related outcomes. Stay tuned for an examination of the 2020-2021 data.

We also encourage interested users to go beyond what we present and use the information that is most relevant and important to the work you are doing. If you find something interesting that we do not highlight, please contact us and we will try to add that in, giving credit where credit is due. If you have ideas for additional graphics or ways of presenting the information, let us know that too and we will do our best to accommodate.