I guess it's a way of handling it that's enabled by the fact that the calendars are electronic. It could be that this way is easier for the school staff, but honestly I have no idea and can't even begin to guess, really.
Even in 2024, schools in major cities experience staffing shortages where there are not enough supposedly-qualified adults to supervise all of the students in their originally scheduled classrooms.
"Solution": class X, Y, and Z all meet in Lunchroom W on Wednesday so one adult can supervise all of them.
