This is the question of the century. Maybe decades from now, there will be a book, then a movie. My only guess is that they have something dirty on our politicians. Something so egregious that they are willing to sacrifice almost everything to keep it quiet.
A bigger picture may be; why is sending kids home for break with homework. It is my opinion, that people learn better when they actually have a break during their break. in my opinion, this is a tactic to prepare kids to think its normal to work all the time. That breaks are never actually breaks.
We burned coal for heat on the coldest of nights when we lived off grid on a ranch in the mountains of colorado. We only used it if we absolutely had to as its super stinky, dirty and gross. We would get maybe two or three big chunks a year that weighed maybe 1-2 lbs. You can go up into the mountains and see the huge mountains of coal from the mines that have shut down. There are also rows of of coke ovens in monument canyon (used in the 19th century to turn coal into smelting iron)
They need to put these in all of the gyms in the cardio equipment. Just think of the power they could store.