As the Trump administration pushes full steam ahead to force U.S. schools to resume in-person education, public health experts warn that a one-size-fits-all reopening could drive infection and death rates even higher. They’re urging a more cautious, flexible approach, which many local governments and school districts are already pursuing. There are too many uncertainties and variables, they say, for back-to-school to be back-to-normal. Dr. Tom Frieden is former head of the federal Centers for Disease Control and Prevention. He says curbing COVID-19 activity in communities is the single most important thing that can be done to keep schools safe.