There is a risk in everything one does in life. Taking reasonable precautions makes sense, but to isolate ourselves and to quit living an active life of physical, emotional, and educational growth is not the answer. I think if humanity had crawled in a hole every time there was a chance of catching an infection or cracking our skulls we would still be living in caves. It is beyond comprehension that someone who would strive to climb Annapurna or K2 with a death rate around 30% is afraid of a virus with a death rate that is closer to 1%, but that seems to be the story. Think about it, every time you drive down the road and pass a vehicle going the other way, you are within feet of death. Risks? Bike riding, swimming, sports?
Get those kids back in school. Let them live their lives and for goodness sake do not scare them with the idea they will die if they get sick.