The Centers for Disease Control and Prevention has relaxed its social distancing guidelines for schools. The federal agency now says students can sit 3 feet apart in classrooms, changing the 6-foot standard that had forced some schools to remove desks, stagger scheduling and take other steps to keep children away from one another.

In recent months, schools in some states have been disregarding the CDC guidelines, using 3 feet as their standard. Studies of what happened in some of them helped sway the agency, said Greta Massetti, who leads the CDC’s community interventions task force.

While there is evidence of improved mental health and other benefits from in-person schooling, “we don’t really have the evidence that 6 feet is required in order to maintain low spread,” she said.

The new guidelines also remove recommendations for plastic shields or other barriers between desks. “We don’t have a lot of evidence of their effectiveness” in preventing transmission, Massetti said. The CDC said 6 feet of distance should still be maintained in common areas, such as school lobbies and when masks can’t be worn, such as when eating. Also, students should continue to be spaced 6 feet apart in situations where there are a lot of people talking, cheering or singing, all of which can spread droplets containing the coronavirus. That includes chorus practice, assemblies and sports events.

The CDC guidance had been problematic for many Utah schools that traditionally had 25, 30 or more children per classroom in closely grouped desks. Some schools adopted complicated, hybrid scheduling, that might, for example, have half a class come to school on some days and the other half on other days.