The monitor, 68-year-old Karen Klein, told police she is happy with the swift and strong community response against the verbal attack, which was captured in a 10-minute video, authorities said at a news conference Thursday.
Criminally charging the boys, all seventh-graders, would require their conduct to rise to the level of a crime, Greece Police Capt. Steve Chatterton said. So far, it has not been found to reach that level.
By Thursday morning, the YouTube video had been viewed more than 1.5 million times, and by midday, an online crowd-funding site raised more than $225,000 to help send Klein on vacation.
Klein said she hopes the boys' parents will view the viral video of the attack and talk to their children about being "a little more respectful." Parents of all four boys are cooperating fully and say their children will be punished, Chatterton said.
In the video, recorded by a student, Klein is seen trying her best to ignore a stream of profanity, insults and outright threats directed at her. At one point in the video, she breaks down in tears.
Klein told NBC's "Today" show Thursday that it took "a lot of willpower" not to respond to Monday's jeers from at the boys riding the bus operated by the Greece Central School District, a suburban Rochester district that's the ninth largest in the state.
"I'm not usually that calm. Just ask my kids," Klein, a grandmother of eight, said during the interview. "I'm sure they don't act that way at home, but you never know what they're going to do when they're out of the house."
Klein said she is "amazed" at the support she has received.
"I've got these nice letters, emails, Facebook messages," she said. "It's like, wow, there's a whole world out there that I didn't know. It's really awesome."
The publicity over Klein's case -- an adult apparently being bullied by youths -- adds a twist to a recent surge in awareness that has brought the issue from the classroom to the stage and screen to the White House.
In September, after 14-year-old Jamey Rodemeyer, not far from Rochester in suburban Buffalo, killed himself after complaining about being bullied about his sexuality, pop singer Lady Gaga decried the loss of another life to bullying, tweeting to millions of followers that she'd take her concerns to President Barack Obama.
This year, the White House held a conference on bullying prevention, estimating that it affects 13 million students, or about a third of those attending school. Obama said he hoped to "dispel the myth that bullying is just a harmless rite of passage or an inevitable part of growing up. It's not."
In April, the documentary film "Bully" examined the problem by following five kids over the course of a school year.
In Klein's case, she didn't report the bullying, but school officials notified Greece police when they learned of it. The school may take disciplinary action.
The school district activated its bullying and violence prevention response team to investigate. At least two other videos showing Klein being taunted by students aboard a bus are known to have been posted online.
"We have discovered other similar videos on YouTube and are working to identify all of the students involved," according to a statement posted on the district's website.