A school cafeteria worker in New Hampshire who was fired for giving a student lunch for nothing has rejected an offer to be rehired.

Bonnie Kimball said she was fired on 28 March by Fresh Picks, a vendor that supplies food to the Mascoma Valley regional high school in Canaan, a day after she gave a student lunch even though he couldn’t pay for it.

Kimball said that when the student’s account showed no funds, she quietly told him “Tell mom you need money”, and provided a lunch.

A manager asked what was on the boy’s plate, she said, then walked away. The next morning the student’s bill was paid.

“His family is very well known in this town and I can guarantee that if I called his mother, she would have come right in and paid the bill,” Kimball said. “But I didn’t want to get her out of work. I know they would have brought the money the next day. The bill was going to get paid.”

A spokeswoman for the Manchester-based company said an employee it did not name violated school and company policy and a district manager terminated the person. But the company said it had offered to rehire the employee, provide back pay and “work with the school district to revise policies and procedures regarding transactions”.

Kimball, who has four grandchildren in the school district, said she had no intention of returning and accused the company of only offering to rehire her “so that it could keep its contract”.

The Mascoma regional school board voted on Tuesday to use the company for another year, despite the controversy involving Kimball.

The Valley News reported that the alleged firing has angered Kimball’s co-workers, some of whom quit in protest. Parents at the school said they were upset by Kimball’s sudden departure and demanded she be rehired. Some even started a GoFundMe campaign for her that had raised more than $5,000 by Friday night.

Kimball said she had also received an outpouring of support on her Facebook page, including from a US Navy Seal and a professional football player.

“When I walked out of the school the day that I got fired, all that was going through my head was that I wouldn’t be able to show my face again. People would think I was a thief,” she said, adding the support since then “makes me feel good”.

“Lord, all the support and TV stations,” she added of the interview requests. “I am like ‘Why are they contacting me?’ I’m still in awe.”

Schools across the country are struggling to deal with how to address students who cannot pay for lunch. A 2011 survey found that a majority of districts had unpaid lunch charges and that most dealt with it by offering alternatives meals.

Last month, federal lawmakers introduced “anti-lunch shaming” legislation to protect students with unpaid lunch bills. The US Department of Agriculture discourages practices that stigmatize students, but allows districts to set their own policies.