Students in Wichita, Kan., public schools can ditch the masks when classes begin.

Detroit public schools will probably require them unless everyone in a room is vaccinated.

In Pittsburgh, masks will likely be required regardless of vaccination status.

And in some states, schools cannot mandate face coverings under any circumstances.

With COVID-19 cases rising nationwide, school districts across the U.S. are yet again confronting the realities of a polarized country and the lingering pandemic as they navigate mask requirements, vaccine rules and social distancing requirements for the fast-approaching new school year.

The spread of the delta variant and the deep political divisions have complicated decisions in districts from coast to coast.

In some states, lawmakers have banned districts from requiring masks despite outcry from medical professionals.

Schools are weighing a variety of plans to manage junior high and middle school classrooms filled with both vaccinated and unvaccinated students.

“I'm so frustrated that it's become a political issue because it shouldn't be. It's science,” said Mary Tuttle, who operates an Indianapolis in-home day care center and has watched the debate in her state over vaccines and masks.

The vaccine has not been approved for children under 12.

If it shown to be safe and effective for younger ages, vaccine manufacturers may seek emergency authorization sometime this fall or winter.

Adding to the concerns is a rise in cases overall — sharply in some states, including Arkansas, which won't let schools require masks. Public health researchers on Tuesday called Arkansas' rapidly climbing infections and hospitalizations a “raging forest fire,” and the state's top health official warned of significant future outbreaks in schools.

Arkansas leads the country in new cases per capita, according to figures compiled by Johns Hopkins University researchers, and it has one of the lowest vaccination rates in the country, with only 35% of the population fully vaccinated.

Weekly tallies by the American Academy of Pediatrics based on state reports show that COVID-19 cases in kids increased nationally in July after a couple of months of declines. The most recent data shows a 1% increase from July 1 to July 15, representing 43,000 additional cases.

American Federation of Teachers President Randi Weingarten said the fact that some states refuse to allow mask requirements “is just plain wrong.” She said the organization has embraced recommendations from the Centers for Disease Control and Prevention, including masking for those who are not vaccinated and other mitigation steps such as 3-feet physical distancing, ventilation and testing.

But school officials say masking decisions have been complicated by conflicting advice from public health officials.

The American Academy of Pediatrics on Monday recommended universal masking in schools, even for those who are vaccinated against the virus that causes COVID-19. The CDC earlier this month recommended mask-wearing indoors only for students and staff who are not fully vaccinated.

“It's frustrating. Parents hear that these are recommendations, and it becomes a delicate dance” because of differing opinions, said Steve Matthews, superintendent of Novi Community Schools, outside Detroit.

“It would be very helpful if there was agreement among the medical community what the approach should be,” Matthews said. When everyone wore masks last year, “it created a sense of community, a sense that we're all in this together. Now it ends up dividing people.”

In Pittsburgh, administrators are proposing that all public school students and staff be required to wear masks indoors to protect younger students and because of “concerns around unknowns from the variant,” spokeswoman Ebony R. Pugh said. Universal masking also protects the privacy of older students who have not been vaccinated, she said.