America's kids are going back to school. Not all of their teachers will join them

Teachers across the U.S. are battling challenges on multiple fronts, and it's driving many to leave. (Megan Jelinger/AFP via Getty Images)

It's a new school year and Jake Miller is not setting up his classroom in central Pennsylvania. He's not getting to know a new group of eighth-graders in his social studies class. After 15 years of teaching, he quit.

"I was accused of teaching critical race theory when I taught about how the Civil War was fought over racism and slavery," he said.