Sex education should begin before children reach puberty. Usually, children receive some basic sex education from the age of 8 or 9. These educations usually involve anatomy, gender and gender roles, gender identity, protection of private parts, and how to deal with sexual harassment and sexual assault.

In the process of children's growth, parents should gradually provide more detailed and complicated sex education content. Before children enter adolescence, they should be educated in reproductive system, sexual behavior, sexually transmitted diseases and contraception. After children enter adolescence, they should be given more in-depth sex education, including sexual health, sexual orientation and sexual autonomy.

In short, sex education should begin before children enter adolescence, and gradually deepen and expand with their growth. Parents should provide an open and inclusive environment, encourage children to ask questions freely, and provide detailed and accurate information to help them better understand and manage their sexual health.