Skip Navigation

REL Central Ask A REL Response

Beating the Odds

September 2019


What is the impact of a four-day school week on student achievement?


Following an established REL Central research protocol, we conducted a search for research reports as well as descriptive study articles to help answer the question. The resources included ERIC and other federally funded databases and organizations, research institutions, academic databases, and general Internet search engines. (For details, please see the methods section at the end of this memo.)

References are listed in alphabetical order, not necessarily in order of relevance. We have not evaluated the quality of the references provided in this response, and we offer them only for your information. Also, we compiled the references from the most commonly used resources of research, but they are not comprehensive and other relevant sources may exist.

Research References

Anderson, D. M., & Walker, M. B. (2015). Does shortening the school week impact student performance? Evidence from the four-day school week. Education Finance and Policy, 10(3), 314–349. Retrieved from
Full text available at

From the abstract:

“School districts use a variety of policies to close budget gaps and stave off teacher layoffs and furloughs. More schools are implementing four-day school weeks to reduce overhead and transportation costs. The four-day week requires substantial schedule changes as schools must increase the length of their school day to meet minimum instructional hour requirements. Although some schools have indicated this policy eases financial pressures, it is unknown whether there is an impact on student outcomes. We use school-level data from Colorado to investigate the relationship between the four-day week and academic performance among elementary school students. Our results generally indicate a positive relationship between the four-day week and performance in reading and mathematics. These findings suggest there is little evidence that moving to a four-day week compromises student academic achievement. This research has policy relevance to the current U.S. education system, where many school districts must cut costs.”

Donis-Keller, C., & Silvernail, D. L. (2009). A review of the evidence on the four-day school week (Research Brief). Portland: University of Southern Maine, Center for Education Policy, Applied Research and Evaluation. Retrieved from

From the ERIC abstract:

“Faced with volatile fuel and energy prices and rising education costs, school districts across the country are considering ways in which to reduce their expenditures and increase efficient use of limited resources. The four-day school week has been proposed as one solution to address budget shortfalls. News reports indicate that districts in several states including New York, Iowa, Minnesota, Ohio, Pennsylvania, Kansas, and Louisiana are considering such a shift in instructional time. Proponents argue that reducing the number of days students attend classes may yield savings in transportation, facilities, and personnel costs.

At present, the four-day school week is being used in more than 120 school districts across the country, in states including New Hampshire, Colorado and New Mexico. Use of the four-day school week also extends beyond our borders to several provinces in Canada, France, and Britain.

This research brief provides a history of the reform and presents a synthesis of the research base, albeit limited, focused on the implementation and impact of moving to a four-day school week schedule. Also included is a discussion of the most commonly voiced concerns.”

Hewitt, P. M., & Denny, G. S. (2011). The four-day school week: Impact on student academic performance. Rural Educator, 32(2), 23–31. Retrieved from

From the abstract:

“Although the four-day school week originated in 1936, it was not widely implemented until 1973 when there was a need to conserve energy and reduce operating costs. This study investigated how achievement tests scores of schools with a four-day school week compared with schools with a traditional five-day school week. The study focused on student performance in Colorado where 62 school districts operated a four-day school week. The results of the Colorado Student Assessment Program (CSAP) were utilized to examine student performance in reading, writing, and mathematics in grades 3 through 10. While the mean test scores for five-day week schools exceeded those of four-day week schools in 11 of the 12 test comparisons, the differences were slight, with only one area revealing a statistically significant difference. This study concludes that decisions to change to the four-day week should be for reasons other than student academic performance.”

Plucker, J. A., Cierniak, K., & Chamberlin, M. (2012). The four-day school week: Nine years later (Education Policy Brief, Vol. 10, No. 6). Bloomington, IN: Center for Evaluation and Education Policy, Indiana University. Retrieved from

From the introduction:

“As Indiana schools continue to face budget cuts and explore ways to reduce expenditures, some may consider the four-day week as an option. In 2003, the Indiana Education Policy Center (now CEEP) released an Education Policy Brief, The Four Day School Week (Chamberlin & Plucker, 2003). In the current brief, the discussion of the four-day week continues, including advantages and disadvantages of the modified schedule, the steps a school might take to make the switch, and recommendations for districts considering the change. Examples of districts that have made the switch are also included. This brief intends to provide information and guidance for school districts and policymakers considering the possibility of a four-day school week.”

Tharp, T. W. (2014). A comparison of student achievement in rural schools with four and five day weeks (Doctoral dissertation, University of Montana). Retrieved from

From the abstract:

“The purpose of this non-experimental, quantitative, causal comparative study was to examine the relationship between student achievement scores on the Montana statewide standardized assessment (MontCAS) from schools that use a four day school week in Montana to student achievement scores on the MontCAS from schools across the state of Montana that follow a traditional five day school week. The MontCAS is the standardized assessment in reading, mathematics, and science adopted by the Montana Office of Public Instruction as a result of mandates from the No Child Left Behind Act of 2001.

In the spring of 2005, the Montana Legislature approved changes to the accreditation standards in Montana by allowing a school to be accredited based upon a total number of contact hours instead of the previous requirement of a minimum number of contact hours and a minimum number of days of instruction. Ten schools made the conversion to a four day week beginning in the 2006–2007 school year. By 2008–2009 there were 22 schools following a four day week calendar and over the next several years, this number doubled every two years. By the 2012–2013 school year, there were over 100 schools in Montana with a four day week.

Data was provided by the Montana Office of Public Instruction on every student from every school in Montana that utilized the four day school week from implementation through the 2012–2013 school year. This data was analyzed by cohort based upon the year of implementation of the four day week in addition to being considered in the composite as the number of students tested in schools with the four day week grew from just over 200 in the spring of 2007 to 2685 in the spring of 2013.

The total percentage of students identified as proficient and advanced was compared to statewide averages disaggregated by cohort and in composite over the academic years of 2006–2007 through 2012–2013.

Findings indicate that student achievement may increase the first year of implementation of the four day week, but over time, student achievement decreases, compared to the rest of the students in the state of Montana.”

Tharp, T. W., Matt, J., & O’Reilly, F. L. (2016). Is the four-day school week detrimental to student success? Journal of Education and Training Studies, 4(3), 126–132. Retrieved from

From the abstract:

“School districts across the United States are implementing four-day school weeks. This study looks at the relationship between student achievement in the four-day school week compared to student achievement in the five-day school week. This analysis focused on a common criteria referenced test given to all students over a period of seven years in a single western state. The study provided conclusive evidence that students in the four-day week did not performed as well, over time, when compared to students in the traditional five-day week settings.”

Thompson, P. N. (2019). Effects of four-day school weeks on student achievement: Evidence from Oregon (IZA Discussion Paper No. 12204). Bonn, Germany: IZA Institute of Labor Economics. Retrieved from

From the abstract:

“Due to increased financial pressures following the Great Recession, a growing number of school districts have switched from a traditional five-day school week to a four-day week schedule. While these shorter school weeks potentially help reduce costs, this study considers the implications these school schedules have on student achievement. This study uses a difference-in-differences analysis using a panel data set of student-level test scores to examine the effects of the adoption of these four-day school weeks on student achievement in the State of Oregon from 2007–2015. I find that these school schedules have detrimental impacts on student achievement, with declines of between 0.044 and 0.053 standard deviations in math scores and declines of 0.033 and 0.038 standard deviations in reading scores. The results suggest that four-day school weeks are more detrimental for the math and reading achievement of boys and the reading achievement of low-income students. Earlier school start times and lost instructional time of nearly three and a half hours a week appear to be the primary mechanisms underlying these achievement losses.”


Keywords and Strings

The following keywords and search strings were used to search the reference databases and other sources:

  • “Four day week” AND “student achievement”
  • Four day school week
  • Four day school week student achievement

Databases and Resources

We searched ERIC for relevant resources. ERIC is a free online library of over 1.6 million citations of education research sponsored by the Institute of Education Sciences. Additionally, we searched Google and Google Scholar.

Reference Search and Selection Criteria

When searching and reviewing resources, we considered the following criteria:

  • Date of the Publication: References and resources published between 2009 and 2019 were included in the search and review.
  • Search Priorities of Reference Sources: Search priority was given to ERIC, followed by Google Scholar and Google.
  • Methodology: The following methodological priorities/considerations were used in the review and selection of the references: (a) study types–randomized control trials, quasi experiments, surveys, descriptive analyses, literature reviews; and (b) target population and sample.

This memorandum is one in a series of quick-turnaround responses to specific questions posed by educational stakeholders in the Central Region (Colorado, Kansas, Missouri, Nebraska, North Dakota, South Dakota, Wyoming), which is served by the Regional Educational Laboratory Central at Marzano Research. This memorandum was prepared by REL Central under a contract with the U.S. Department of Education’s Institute of Education Sciences (IES), Contract ED-IES-17-C-0005, administered by Marzano Research. Its content does not necessarily reflect the views or policies of IES or the U.S. Department of Education nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.