The rules where I live are vaccines are permitted to take the mask off. Yes, viruses don't discriminate but shear numbers do. Not only that but as ages get younger death rates and serious complications decline to extremely low numbers. The young fight off the virus very well. There is an uncommon study done in Georgia where infection rates were compared between schools with a mask mandate and schools with none. The study found no difference in the spread of Covid 19. Mind you you the sample size was 90,000 so plenty big enough.