One in three states has already prohibited COVID-19 vaccine mandates in schools — even before the FDA has fully approved vaccines for children.

Why it matters: The Biden administration hoped to rely on schools as a “trusted messenger” in support of coronavirus vaccines, but schools have become a political battleground as the Omicron variant roars across the U.S.

The big picture: The laws passed to date take different approaches, but the result is that schools in 17 states cannot require COVID-19 vaccines, according to the latest data compiled by the National Academy for State Health Policy.

For some states, that’s the case even as schools expect students to receive other recommended childhood vaccinations like measles, polio and chickenpox.