CNN  — 

Millions of American kids will head back to classrooms in the coming days – just after new pediatric Covid-19 hospitalizations reached an all-time high.

And that has many parents wondering what’s safe as the Omicron variant sweeps the country.

“We fear that it’s going to get a lot worse, between getting together for the holidays and then getting back to school,” said Dr. Stanley Spinner, chief medical officer at Texas Children’s Pediatrics & Texas Children’s Urgent Care in Houston.

Some cities and school districts are taking aggressive new measures.

Several Atlanta-area school districts are delaying in-person classes and starting 2022 with remote learning.

In Washington, DC, all public school students and staff must show proof of a negative Covid-19 test before returning from winter break.

In New York City, public school students who test positive will get a week’s worth of at-home tests so they can know when it’s safer to return to school.

But do vaccinated students still need to wear masks? What should families do if they can’t get Covid-19 tests? Should activities like choir and basketball practice be sidelined until the Omicron surge passes?

Here’s how several pediatricians and health experts answered some of the most critical questions from parents:

Should kids not return to classrooms just yet?

Health experts are divided.

In areas of very high transmission, it might be too early to resume in-person learning, pediatrician Dr. Peter Hotez said.