When the new order takes effect, all school staff must also be vaccinated and will no longer have the option to take weekly tests as an alternative.
Newsom pointed to the success of the San Francisco school district, which already has a staff vaccine requirement, and has only reported 46 new COVID infections among its staff of nearly 10,000 since in-person school resumed in August.
"San Francisco Unified School District has overwhelmingly succeeded in getting staff across the spectrum vaccinated," he said.
Until now, Newsom had left the decision on student vaccine mandates to local school districts, leading to a variety of different orders across some of the state's largest districts. Five districts in California have already imposed their own requirements, including Los Angeles, the nation's second-largest school district, which is set to take effect in January.
Under Newsom's mandate, those districts can proceed with their plans and "accelerate" the requirements.
Dr. Peter N. Bretan, president of the California Medical Association, said his organization “strongly supports” the governor's decision.
“This is not a new idea. We already require vaccines against several known deadly diseases before students can enroll in schools,” he said in a statement. “The Newsom administration is simply extending existing public health protections to cover this new disease, which has caused so much pain and suffering across our state, our nation and the entire globe over the last 18 months.”
Newsom has made it a point of pride to be the first in the nation to issue a variety of pandemic-related school mandates.
In August, California became the first state to require all teachers and staff in K-12 public and private schools to get vaccinated or undergo weekly COVID-19 testing. Newsom also issued a school mask mandate earlier in the summer for indoor classes that applies to all teachers and students.
"I believe we are the first state in America to move forward with this [new vaccine] mandate, but I do not believe by any stretch we'll be the last state," he said.
This post includes additional reporting from KQED's Holly McDede and The Associated Press.