Secretary of Education, Betsy DeVos, finally made a point in her whole career that actually made sense. When she's asked about schools following CDC guidelines in the fall, to open up for students, DeVos says that "Dr. Redfield has clearly said these are recommendations and every situation is going to look slightly different."
Oh wait, her answer was actually another person's answer. So that means Betsy DeVos and the job of Education Secretary is still as pointless as it always was.
When it comes to schools opening in the fall, we're still 1-2 months away from that and anything could happen.
Every city and school will present themselves with their own situations and there is no single answer other than this - use common sense.