Tell them that if they get an "A", and someone else who doesn't want to do homework gets a "D" (which just is NOT fair), then to make it FAIR, they will just get a "B minus" no matter how hard they study....THAT is socialism to a kid.
Better yet, on the first day of class, the teacher will tell all the young skulls full of mush that everybody gets a C no matter how hard they work. BUT, one of the them will become a member of the nomenklatura and must earn that role by not dissenting and by sucking up. The fortunate nomenklatura can then appoint two people to key classroom positions who must be eager to please their patron. Some of the kids would be sent to an hours-long line to buy a moldy week-old loaf of bread.
It wouldn’t take long for reality to hit them.