When Bellingham Christian School took a day off because of good weather, it made national news. I even heard something about it on NPR.
Opposite idea from having school run all summer and no summer vacation. A day off can be useful from time to time. Change from the routine for other kinds of learning. Time for friends and family, time for even resting. In the case of summer vacation, it's often time for travel.
I heard about a school, somewhere in USA taking a day off to see the sun when I was in grade school. That school was in a place with lots of clouds; similar to Bellingham. Good to hear of it happening again, this time in the town I live in; often cloudy Bellingham.