Seems like Germany has a good idea to vary it, to reduce pressure on travel. However we should think bolder still, reimagine the whole timing of the academic year which derived from nineteenth century traditions when children helped plant and gather crops. Now instead we should consider climate change, and July became too hot for comfortable travel in most of continental europe. So it would be better to have long holidays in May-June and maybe September, while also investing in cooling for school buildings (maybe more practical than for small homes).