The four-day school week has gained popularity around the U.S., with several school districts in Washington state opting into the schedule. However, most of the schools operating on the schedule are in rural Eastern Washington districts, and experts say it’s uncharted territory as to whether the concept would work in Western Washington.

The state legislature voted in 2009 to allow four-day school weeks, but with strict conditions: Only five districts in the state could operate a four-day school week at one time. Of those five districts, two could have student populations of under 150 students, and three could have between 150 and 500 students.

“Washington state has one of the more strict laws (around four-day school weeks),” said Georgia Heyward, a research analyst at the University of Washington-Bothell’s Center on Reinventing Public Education. “They have a higher bar of accountability than other states.”

Based on those requirements, 2018 enrollment numbers show several dozen districts in Western Washington would qualify, most of which are on the Olympic Peninsula, in the southwest interior, or off Highway 2 in the Cascades.

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On the west side of the mountains, the four-day school week hasn’t taken off yet. Eatonville School District floated the idea of a four-day school week in 2011, but it never came to fruition.

Five school districts in Eastern Washington will operate on a four-day week this school year: Waterville School District in Douglas County, Selkirk and Cusick School Districts in Pend Oreille County, Paterson School District in Benton County, and Bickleton School District in Klickitat County.

Waterville, which is about 25 miles northeast of Wenatchee, is making the move to a four-day week this year to try and increase staff recruitment and retention, boost attendance, and improving the classroom experience.

Nationally, there are some larger school districts that have tried the concept, including several districts in Idaho and Colorado that are within 30 minutes of urban centers and two Georgia school districts that are partially consolidated and have over 10,000 students combined.

There’s not a lot research on how those larger districts are faring under the system compared to smaller districts, according to Heyward. However, general research on the four-day school week has shown that discipline rates go down slightly, and families tend to be happy with the schedule change. Cost savings are a mixed bag, and in some instances, districts have ended up spending more than before the switch, according to Heyward.

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The motivations for larger districts moving to a four-day week may also be different than small, rural districts. For example, districts in large, urban areas may be less concerned with long commute times, sports travel eating into class time, or attracting teachers.

Heyward said larger districts may see the schedule shift as a way to innovate though opportunities for internships or community college classes that may not be present in rural communities.

“There’s a lot of opportunities to use that fifth day in ways to extend student learning,” Heyward said, “and you see that motivation built in when looking at the four-day school week.”