A South Florida teacher said she was fired after she refused to give a student a 50 percent grade on homework that was not turned in.

Port St. Lucie teacher Diane Tirado said students should not get credit for work that was never handed in, according to CNN.

Tirado said she strives to provide motivation and inspiration to her students. Tirado has been a teacher for years, but she started at West Gate K-8 School in August as an eighth-grade history teacher.

"Teaching is a calling for me," she said.

Tirado said she assigned an explorer notebook project that she gave the students two weeks to complete.

When several students did not turn in their assignments, Tirado said she found out about a "no zeros" policy, in which the lowest possible grade allowed to be given is 50 percent. She said the policy is in the student and parent handbook.

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Tirado said she asked administrators, “What if they don't turn it in?”

She said the reply she received was, “We'll give them a 50.”

Tirado was terminated Sept. 14, but there’s no cause mentioned in the letter from the principal, since she was still in her probationary period.

On her last day of school, Tirado wrote a message on a whiteboard that read, “Bye, kids. Mrs. Tirado loves you and wishes you the best in life! I have been fired for refusing to give you a 50% for not handing anything in.”

Tirado sent a picture of the message through a class app and her students responded.

“You were right about not giving people 50s, because why would you give them half credit for doing nothing?” one student wrote.

Tirado posted the same whiteboard photo on Facebook Sept. 15.

“I’m so upset because we have a nation of kids that are expecting to get paid and live their life just for showing up and it’s not real,” she said.

Tirado hopes her actions will motivate policy change.

“A grade in Miss Tirado's class is earned," she said.

“There is no district or individual school policy prohibiting teachers from recording a grade of zero for work not turned in,” Kerry Padrick, West Gate chief information officer, said in a statement. “The district's uniform grading system utilizes letter grades a-f, numerical grades 100 to zero and grade point averages from four to zero.”

Tirado said she was told never to give a student a zero.

"The reason I took on this fight was because it was ridiculous," Tirado said in a Facebook post Tuesday. "Teaching should not be this hard. Teachers teach content, children do the assignments to the best of their ability and teachers grade that work based on a grading scale that has been around a very long time. Teachers also provide numerous attempts to get the work collected so they can give a child a grade. By nature, most teachers are loving souls who want to see students succeed. We do above and beyond actual teaching to give them the support they need. Are we perfect? NO. We make mistakes like all other human beings, but I know teachers work their butts off to help children to be the best people they can be!!!"