While every school district has its own rules for containing COVID-19 on campus, the CDC has also released recommendations to help schools stay safe.
The Phoenix Union High School District announced the campaign last week in an attempt to get 85% of its school community vaccinated.
As of last month, 76% of city employees had been vaccinated against COVID-19, while 546 employees had requested an exemption from getting the vaccine.
While the original strain of the virus had a lower infection rate among kids, the Delta variant is twice as contagious and more likely to infect children.
As of Monday, 55.2% of all state residents had received at least one dose of a COVID-19 vaccine, and 3.4 million had been fully vaccinated.
The company cited flu season, the spread of the COVID-19 Delta variant, and the high hospitalization rate among unvaccinated as reasons for the requirement.
The COVID-19 vaccine is now available to anyone 12 and older at a number of pharmacies and at any of Arizona's state-run vaccination sites.