They have been given thousands to buy it all, so their choice really. It doesn't help much with communication, as it is proper PPE, so I'm not sure whether it is helpful for teaching or not.
If they are not considered "safe" (whatever that might mean) what's the alternative to sending them to school? Let's start getting real here. Since we're in school, hands up all those who believe it is sensible and necessary to keep schools closed indefinitely?