The chemicals can be found in such items as shoes, furniture, flooring, carpeting and toys.
"This has no place in Orange County," Representative Katie Porter said.
"You've gone outside of your curriculum to introduce a racist exercise. Who authorized that?," Loudoun NAACP Chapter President Michelle Thomas said.
Officials credited another student and a school bus driver for finding the gun in the boy's backpack.
The three middle schoolers also gave flowers to each of the 70 female staff members at Summit Trail Middle School.
Mumps, which the MMR vaccine can prevent, can cause complications, including brain swelling and meningitis.
The Pasadena Independent School District said in a statement that Jose Armando Lopez Solorio's job did not require direct contact with children.
Wondering what all the ribbons are in Bitlife? Check out our complete list of Bitlife - Life Simulator ribbons plus tips for how to get them.
"Forcing our children to choose between an environment in which they feel unsafe or staying home was not an option."
Authorities said one student specifically mentioned wanting to replicate the Columbine shooting in their Instagram messages.
"It's our history. We live in a southern state, and if we were doing it for hate we wouldn't be wearing it."
"She said that yes, she locked him out. That she felt she was in danger, so she wanted to make sure everyone was safe so she locked him out."
The school bus set alight after a car crashed into the back of it.
The female student wrote "I would like to state I am not anti-Semitic in any way, I hate all races equally" beneath a social media post of the image.
The book features a romance between two gay bunnies and spoofs a book created by Karen Pence and her daughter.
An image of the handgun, a Glock, was posted online. The magazine appeared to be fully loaded.
The songs, which appeared on the popular music sharing website SoundCloud, were shared by a user called "Lil Plantation."
Patricia Cummings, who taught at a school in the Bronx, claims she was discriminated against by New York City and others because she is white.
"I'm not shocked, I'm disgusted, but I'm not shocked."
While violent crime in China is unusual and attacks on children even rarer, there has been a marked uptick in such incidents over the past decade.
Wanda Barzee, who pleaded guilty to helping her husband kidnap Elizabeth Smart in 2002, was released from prison earlier this year.
Public education workers are leaving their jobs at the fastest rate ever recorded by the Department of Labor.
More than 25,300 students had gunfire incidents on campus, 94 people were shot and 33 people were killed in 2018.
"He's done working with our district."