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SHAWNEE, Kan. – A Kansas father said he is upset with the terms his 13-year-old daughter’s school is using when it comes to sex education.

WDAF, our sister station in Kansas City, reported he wouldn’t have known the words and phrases on posters in school if his daughter had not taken a picture to show him.

Mark Ellis said he originally thought it was a student prank at Hocker Grove Middle School in Shawnee, Kansas.

He said he contacted the principal after he saw the poster with words like “oral sex” and “grinding.”

Ellis said the principal told him it was teaching material, according to WDAF.

“It upsets me, and again, it goes back to who approved this,” he told WDAF. “You know this had to pass through enough hands that someone should have said, ‘Wait a minute, these are 13-year-old kids, we do not need to be this in-depth with this sexual education-type of program.'”

WDAF reported district spokeswoman, Leigh Anne Neal, said the poster should be seen in the context of a bigger curriculum, which she calls “abstinence-based” for students in middle school.

“The poster that you reference is actually part of our middle school health and science materials, and so it is a part of our district approved curriculum,” Neal told WDAF. “However the item is meant to be part of a lesson and so certainly, as a standalone poster without the context of a teacher-led discussion, I could see that there might be some cause for concern.”

Ellis said he doesn’t think it should be part of the curriculum and it should be changed.

He told WDAF if it doesn’t change, he plans to remove his daughter from the sex education classes.

MORE: See more on this story from WDAF