A school bus monitor who was shown in a video being relentlessly bullied by a group of boys said Friday she will retire.

Karen Klein, a 68-year-old grandmother, told The Associated Press that the decision to leave the job she held for three years was tough but wasn't based on her now infamous encounter with the mean-spirited seventh-graders, who tormented her with profanity, insults and threats during a bus run as the school year wound down in June.

A 10-minute video of the episode went viral and spurred an outpouring of more than $700,000 in donations for Klein from all over the world.

'I'm not quitting because of what happened.'—Karen Klein

A Toronto man, Max Sidorov, was so moved by Klein's story that he started an online campaign with the goal of raising $5,000 to send her on a vacation. The fundraising site Indiegogo listed the total amount raised at $703,833. A spokeswoman for the site said more than 30,000 people contributed, with donations coming in from at least 84 countries.

"I'm not quitting because of what happened. That's not it," Klein said from her home in the Rochester suburb of Greece. "I enjoyed working with the kids. But I guess it's my time to leave. That's what I've decided."

Although her mind is made up, she said she has yet to submit the paperwork that would make her retirement official.

Before becoming a bus aide, Klein drove a school bus for 20 years.

She said she'll keep busy in her retirement, perhaps volunteering with organizations that help people touched by bullying or suicide.

Klein's oldest son killed himself 10 years ago, making all the more appalling one of the students' taunts: "You don't have a family because they all killed themselves because they don't want to be near you."

The cellphone video, posted online, shows Klein trying her best to ignore the abuse.

The Greece school district has suspended the four students for a year.