Aug. 7, 2014 at 7:00 PM ET
A high school textbook used to teach teens about the birds and the bees is ruffling some feathers.
Parents in Fremont, California, are petitioning to have a sex-ed book removed from schools this fall, arguing it is too racy for the ninth-graders it is meant to educate.
More than 1,500 parents have signed a petition online to have the book, "Your Health Today," removed from the classroom, stating that it includes references to vibrators and bondage and is "extremely inappropriate" for 13 and 14-year-olds.
The book was approved by the school board in June as an updated text to be used in health classes in the Fremont Unified School District, to replace a previous textbook which was 10 years old.
The school board has defended the textbook, and said there are no plans to remove it from the curriculum.
"The teachers felt here is what California requires, here are the standards, this is the best match for it," James Morris, superintendent of the Fremont Unified School District, told TODAY.
Sex educator Elle Chase called the book a modern text for modern times.
"I don't know what kind of sexual education you got, but a teenager took a blackboard and showed me how babies were made," she said.
The authors of the textbook told TODAY the book is targeted to college freshmen, but believe the material is still appropriate for a younger audience.
Some parents agreed.
"There is nothing there that's going to make him go exploring [more] than they have access to on their smartphones or on the Internet — nothing made me feel that it was inappropriate," parent Becky Bruno told NBC Bay Area.
Parents who are upset about the book can reportedly have their children opt out of health class.
Meanwhile, the textbook has elicited nervous laughs from some students questioning whether they're ready for the material.
"Like ewwww," said Kate Topham. "I don't really feel like I need to know about that right now."
School is back in session on Aug. 27.