Nearly a quarter of K-12 teachers experienced a gun-related school lockdown last year, while 18% are "very" or "extremely" worried about a shooting at their school, a new Pew Research Center survey found.

Why it matters: There's a massive teacher shortage, with many factors contributing to high turnover, including low pay, culture wars and fears about physical safety.

Driving the news: Pew's poll, released Thursday, paints a somber picture of the atmosphere inside American schools.

• 8% of the 2,531 teachers polled said they'd been in more than one gun-related lockdown last year.
• 39% said their school had done a fair or poor job of giving them the training and resources they need to deal with an active shooter.
• 49% would welcome having police officers or armed guards in their school as a preventative measure.

Zoom in: Among the teachers polled, the largest percentage who said they'd been in lockdown taught high school (34%) and in urban areas (31%).

• Among all teachers, 69% said the best way to prevent school shootings would be to improve mental health screening and treatment.
• 33% favor metal detectors in schools, while 13% want teachers and administrators to be able to carry guns.

The latest: The parents of Michigan school shooter Ethan Crumbley, who killed four people, were sentenced to 10 to 15 years in prison Tuesday for involuntary manslaughter.

• They're the first parents in the U.S. to be held criminally responsible for their child's mass shooting.

The big picture: The number of school shootings broke records in 2021, 2022 and 2023 — and this year is on pace to set another record, per CNN.

• "There were at least 82 incidents in 2023, but 2022 was one of the deadliest years, with 46 fatalities," according to CNN's analysis.
• 2022 was the year of the mass shooting at Robb Elementary School in Uvalde, Texas, which killed 21 students and teachers.

Between the lines: Teachers aren't the only ones who are terrified.

• A majority of students and their parents also live in fear of a shooting at their school, an earlier Pew survey found.
• Those fears have been linked to a rise in anxiety and depression in kids.

Follow the money: There's a gold rush to sell security equipment to schools, with vendors tripping over one another to win contracts.

• "I have principals and school security directors tell me they're so bombarded with pitches and overwhelmed with the noise, they don't know who to listen to," Kenneth Trump, a school safety expert and consultant, tells Axios.
• The latest approach involves building "layers of security" — everything from AI weapons detection to bullet-resistant glass coatings to panic buttons that teachers wear around their necks.
• "Parents all want shiny objects," said Trump (no relation to the former president).

The bottom line: It's been 25 years since Columbine (13 murdered), more than 11 years since Sandy Hook (26 murdered), and six years since Marjory Stoneman Douglas (17 murdered), with no clear solution in reach.

Methodology: Pew's findings are based on an online survey of 2,531 K-12 public school teachers conducted Oct. 17 to Nov. 14, 2023, by RAND, which used its nationally representative American Teacher Panel.