In the Cherry Creek School District where she worked, students can receive a free or reduced lunch under a federal programme if their household income is below a certain level.
Students who do not qualify for a free lunch under the programme receive only a slice of cheese on a hamburger bun and a small drink of milk.
Some students do not qualify for either programme and must pay for school lunches.
Curry says she helped these children "whose parents make too much money to qualify, but a lot of times they don't have enough money to eat."
Despite being fired, Curry says she stands by her actions.
"If me getting fired for it is one way that we can try to change this, I'll take it in a heartbeat."
Following the school's decision, Curry set up a Facebook page - No Child Goes Hungry - to campaign for a better school lunch programme.
"While I know that what I did was legally wrong, I do not feel bad about it and I would do it again in a heartbeat," she wrote on Facebook.
"I will never understand how the "best" country in the world considers a cheese sandwich to be adequate nutrition for a child. I will never understand how one of the richest countries in the world cannot provide lunch for its children."
She has received numerous messages of support on the No Child Goes Hungry page.
Her story has prompted other people to come forward, saying they also risked being fired for feeding students.
Dakota Valley Elementary School released a statement following Curry's termination of employment, outlining school policy.
"The law does not require the school district to provide the meal to children who have forgotten their lunch money, that is a district decision. According to our practice, we provide hot meals to students the first three times they forget their lunch money and charge their parents' accounts. The fourth time, we provide a cheese sandwich and milk," the school said.
"The district has worked to keep lunch prices low and still meet the federal nutrition requirements. The costs of our lunch program are not covered by the prices we charge."