ARROYO GRANDE, Calif. – Atheist groups are attacking a California science teacher after getting word he is presenting students with evidence on both evolution and creation theory.

Arroyo Grande High School science teacher Brandon Pettenger reportedly presented students with “both sides of the argument” regarding the beginning of life on Earth – evolution and creationism – to give his students the opportunity to craft their own beliefs and understanding, Christian News reports.

A family of a student in Pettenger’s class took issue with his even-handed presentation of evolution and creationism – which featured the popular debate between Bill Nye the Science Guy and creationist proponent Ken Ham – and initially contacted the teacher with their concerns, according to the news site.

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“I understand that you might be worried I am teaching religion in a public school science class, which is not the case,” Pettenger wrote in response to the parental concerns. “There is debate within the scientific community about how to answer the question where did life come from. I feel it would be a disservice to my students not to present both sides of the argument.”

“We are investigating the main theories that are presented in this debate and the evidence used to support those claims,” Pettenger said. “It is up to each student to decide for themselves which side they believe based on the evidence.”

That answer apparently didn’t sit well with the family, who then contacted the Freedom from Religion Foundation and the Richard Dawkins Foundation for Reason and Science, which sent a letter to Lucia Mar Unified School District superintendent Jim Hogeboom to demand Pettenger present only evolution to students.

“This isn’t an anti-religious stance, this is about my son learning science,” an unidentified parent told CalCoastNews.com. “My son has been upset and frustrated about this since day one. He loves school but he hasn’t wanted to be in this class.”

FFRF and RDFRS contend it’s illegal for Pettenger to talk about creationism, and that there’s really only one side of the debate.

“We understand that Mr. Brandon Pettenger is attempting to ‘present both sides of the argument’ regarding evolution in his public school classroom,” according to the groups’ letter to the district. “Any attempt to teach that there is a controversy about evolution is similarly fraught with legal peril. Evolution is as much a fact as gravity. There are not two sides of the evolution argument for Pettenger to present.”

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“[T]here is simply no controversy. There exists only scientific fact and evidence, and a religious belief that rebels against such evidence,” the letter reads. “One can, indeed must be taught in public schools. The other cannot.”

The atheists called on school officials to put a stop to Pettenger’s two-sided discussion and to impose some sort of “appropriate disciplinary action,” Christen News reports.

District officials, of course, quickly jumped to comply with the atheists’ demands.

Arroyo Grande principal Conan Bowers told the complaining family he was unaware that creationism was taught in Pettenger’s science class, and that he “would put a stop to it immediately,” the local atheist group, Atheists United San Luis Obispo, told KEYT.com.

“We are very pleased the principal is committed to stopping the teaching of creationism at his school and we’re hoping all schools are making sure of the same,” David Leidner, board member with Atheists United, told the news station.

And it seems like district officials are on the same page.

“Our state standards do not have creationism in there,” Tom Butler, assistant superintendent of curriculum and instruction, told KEYT. “Our board policy clearly states our science teachers are not supposed to be teaching that.”