China's education system has long been criticised for its lack of sex education, but a series of textbooks published to address the issue has left parents and critics dumbfounded.
Published as part of a series called Cherish Life in 2010, the books explain how babies are made with illustrations of male and female reproductive organs and a couple having sex.
The graphic illustrations are accompanied by the captions "Daddy and mommy love each other", "Daddy's penis enters mommy's vagina" and "Daddy's sperm enters mommy's uterus".
The brutally honest education material has left parents shocked, and understandably embarrassed.
One mother in Zhejiang province who saw the book in a second-hand market at her child's school was quoted by South China Morning Post as saying: "Is it reasonable for a textbook to be compiled like this? I blush reading it".
A post she uploaded on social media has since gone viral, and netizens can't seem to agree on what the best approach is when it comes to sex education. Some applauded the books for being progressive and honest, while others felt the series was too graphic for children in primary school.
The books, which also touch on topics such as gender equality, prevention of abuse and homosexuality, was published by Beijing Normal University for pupils aged six to 12.
And while the textbooks are not official teaching materials in schools, South China Morning Post reported that it has been used in 18 primary schools in Beijing.
Schools in China are often criticised for avoiding the topic of sex in classrooms. Those that teach sex education are also said to be providing inadequate information on it.
Experts have blamed the lack of awareness for sexual assaults on children, the lack of birth control and the spread of infectious diseases among young adults. A CNN report last year stated that many young women who got abortions in China thought that abortion was their primary form of birth control.