Secretary of Education Miguel Cardona encouraged students to get back in the classroom Tuesday morning.

"At this point, we're talking about making sure students have an opportunity to be in the classroom safely and making sure our staff feel safe going to work...it's time to make sure we do everything we need to do to focus on our students being in the classroom safely," Cardona said.

Cardona also said that he supports requiring teachers to get vaccinated, but the federal government can't require that or mask-wearing.

It's up to the states.