(CNN)Chicago teacher Kimber Bermudez was on a flight to Florida to visit her parents when a friendly passenger asked her what she does for a living.
Passengers overhear a teacher talking about how her students need school supplies and open up their wallets
She told him she was a teacher and how much she loved her job teaching her first graders at Carlos Fuentes Charter School.
Almost half of the students at her school have limited English skills and 87% are classified as low income. But, she told the man, about the close-knit community at the charter school and how it eases some of the burdens by providing free breakfast and lunch and after school programs.
"I'm known as a talker," Bermudez told CNN. "I'm always the one that I will just start talking to anyone. That's just my personality."
The man asked for her work contact information because his company likes to make donations to schools like hers.
What Bermudez didn't realize was that others were listening. She felt a tap on her shoulder from the man sitting behind her.
"The funny part was, the man apologized to me for listening to my conversation," she said. "I realized that he had money in his hand and I didn't know what he wanted me to do with it."
He told her to "do something amazing with it."
Bermudez didn't count the money right away, but she saw a $100 bill on top and burst into tears.
"My parents always taught me not to count money in front of people because it's rude," she said.
Later, she realized that he had given her $500.
When the plane landed, two more men told her they'd heard what they said and wanted to help, Bermudez said.
The man sitting across from her gave her $20 and a man in front of her gave $10. It was all of the cash they had in their wallets.
Bermudez said she wasn't asking for donations, so the generosity caught her by surprise.
Bermudez says she doesn't know who the men on the plane were, but she posted the story on Facebook because they deserved to be recognized for their kindness.
She said she'd love to find them and thank them personally.
Bermudez plans to use the money to buy Spanish and English language books and other classroom material.