The Four Day School Week

I did not know until this morning that the four day school week was a thing in some western states, but turns out that it’s common enough that RAND has done a report about it:

The results point to trade-offs in the 4dsw model. Analysis of data from five states—Idaho, Missouri, New Mexico, Oklahoma, and South Dakota—indicates some evidence of educational harm: The test scores for 4dsw districts improved but did so more slowly than they would have if the same schools had maintained a 5dsw. On the other hand, families and students in 4dsw districts—which are primarily in rural communities in the Western United States—reported highly valuing the extra time that the four-day schedule allowed the family to spend together.

I would imagine that childcare issues would loom large in contexts that included two-earner families and single-parent families, but otherwise I lack particularly strong opinions on this. Thoughts?