FOND DU LAC - A longtime educator at a Lutheran high school in Fond du Lac was told to resign or he would be terminated for teaching about the global problem of female circumcision in his freshman geography classroom.

Daniel Dettmann resigned from his 24-year teaching position at Winnebago Lutheran Academy on Tuesday. He said he was asked to do so because of subject matter the school board deemed inappropriate.

“The school board decided it would be best if the school and I parted company,” Dettmann said.

His son, Corey Dettmann, confirmed that his father was asked to leave for briefly speaking about female circumcision in the context of a geography class discussing different cultures in the Middle East.

Dettmann, 56, said he had touched on the topic with his students for at least a decade and no one ever complained about it, until now. He was told it offended two female students, as well as a third student who was not in the classroom but heard about the lesson.

“I believe it is appropriate subject matter because it is a rising problem in the U.S. and young people should be aware of it,” he said.

As word spread on social media about Dettmann's departure from the school, Corey Dettmann posted a Facebook message on his own page to set the record straight. It has since been removed. His father, he says, is not on social media.

The ritualistic cutting or removal of a young girl’s external genitalia occurs mostly in parts of Africa, the Middle East and a few countries in Asia. In an op ed piece that appeared last December in USA TODAY, Wisconsin Congressman James Sensenbrenner said he would introduce legislation this year to ban the act in the U.S.

According to a report by the U.S. Centers for Disease Control and Prevention, more than 500,000 women and girls have either undergone, or are at risk of undergoing the procedure. On May 19, the U.S. House of Representatives passed a resolution that denounces female genital mutilation/cutting as a violation of the human rights of women and girls. It urges the international community and federal government to increase efforts to eliminate the harmful practice.

The school board told Dettmann they felt they could no longer trust his ability to pick out subject matter that was in line with the school’s and the church’s teachings, he said.

According to the high school’s website: “Winnebago Lutheran Academy exists to glorify God by nurturing the growth of every student to live and serve as Christ’s child within their families, congregations and communities.”

The academy's Board President Dan Loest said neither the board nor the school will comment on the issue at this time. A parent of one of the students who complained also declined to comment and the others could not be reached for comment.

The academy participates in Wisconsin’s Parental Choice program and receives state funding to provide vouchers to students to attend school. Wisconsin's standards for geography state students should learn to “evaluate the effect of culture on a place and time” and “explain how and why people view places and regions differently as a function of their ideology, race, ethnicity, language, gender, age, religion, politics, social class, and economic status.”

The parochial high school currently enrolls 283 students and of those 70, or 24.7%, are voucher students, according to Wisconsin Department of Public Instruction. About 40 Lutheran congregations and 15 area parochial elementary schools feed into the school.

Although Dettmann says he was told by the board that he was warned and reprimanded several times, he said these claims are untrue. He never received any verbal or written communication regarding his curriculum choices in the past.

He does recall being talked to in March about subject matter he shared with students that involved how cultural norms differed from country to country, and what was appropriate in some areas of the world was unacceptable in others.

“I gave a list of 72 examples, things like food, what people wear, how you greet people and there was an objection to some hand gestures I mentioned,” Dettmann said. “To be frank, when I thought it over, I could see their point.”

The 56-year-old headed the school's social studies department and has taught consumer economics, financial planning, American government, sociology and world geography. He served as class of 2019 adviser, and led the academic bowl team and student council.

Kelci Jo Henning, a 2011 academy graduate, said Dettmann was one of the most loved teachers at the school and had a way of keeping students engaged in what he was teaching.

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“His job is to teach about history and current events and the issue of female circumcision is part of that,” Henning said. “Just because it made someone feel uncomfortable he lost his job. These things are not comfortable to talk about but they are necessary.”

Henning said they were only taught abstinence in high school health class — nothing about sex education. Corey Dettmann said some sex education is taught in Lutheran grade schools, depending on the school.

Of the Lutheran synods in the state, Wisconsin Evangelical Lutheran Synod is considered one of the most conservative synods. As a male employee of the school, Dettmann was classified as self-employed and a minister of the gospel. Female teachers, on the other hand, are not self-employed because they cannot be ministers in the church. According to WELS church doctrine, responsibility involves: “headship for a man, including authority, and submission for a woman.”

The Lutheran Church was involved in another recent issue that drew controversy. Sheboygan Lutheran High School valedictorian Nat Werth was not allowed to give his speech at graduation because he talked about his troubles as a gay student and how he was not allowed to join the school dance team because he was gay.

Corey Dettmann says he’s angry his father was made to feel shame for what he was teaching, and the administration used Bible passages to do so.

“My dad has a strong faith and he doesn’t have any ill will toward his church and isn’t bitter. He is just trying to figure out his life right now,” he said.

Since his parting with the school, Dettmann says he’s had colleagues, students and parents offer support. Several persons who had affiliations with the academy were contacted by USA TODAY NETWORK-Wisconsin, but declined to be interviewed for fear of retribution, they said.

Dettmann said he wishes the academy continued success in the future. The school has put in a contingent offer to purchase a parcel of land located on the city’s south side near U.S. 151 to build a new school.

“I think God is in charge and he is clearly telling me he is in charge, and I look forward to the next chapter in my life,” he said.