Online self-paced high-school class size and student achievement

  • Chin-Hsi LinEmail author
  • Jemma Bae Kwon
  • Yining Zhang
Research Article


In the traditional brick-and-mortar classroom, small classes are generally perceived as desirable, but the benefits associated with particular class sizes in online education have not yet received much scholarly attention. Using a dataset of 10,648 enrollment records generated during the 2013–2014 school year at a state virtual school in the Midwestern U.S., this study examined the relationship between class size and student learning outcomes. The results of hierarchical linear modeling with fractional polynomial analysis suggest a reverse-U-shaped relationship, in which increasing online class sizes had a positive impact on achievement until the number of students reached 45, but a negative one if numbers increased beyond that level. At the subject level, similar reverse-U-shaped patterns were observed in math, social science, and other subjects, but not in English, foreign languages, or science.


Online learning Class size Student achievement Virtual school 



This study was supported by a fellowship provided from the research site.

Compliance with ethical standards

Conflict of interest

Chin-Hsi Lin received a fellowship from the research site to conduct the study. Jemma Bae Kwon is currently working at the research site, but she had no control over the data, and she was not involved in the data analysis. Yining Zhang has NO affiliation or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript.


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Copyright information

© Association for Educational Communications and Technology 2018

Authors and Affiliations

  1. 1.The University of Hong KongPokfulamHong Kong
  2. 2.Michigan VirtualLansingUSA
  3. 3.Michigan State UniversityLansingUSA

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