Sex education for preschool and primary school children is extremely necessary and important to help children protect themselves, when the problem of pedophilia and child sexual abuse is increasingly receiving attention.

Biologically, a person's sex is determined by sex chromosomes, hormones, internal reproductive organs, and external genitalia. In addition, determining whether a child is a boy or a girl is based on many other factors such as social behavior, male and female attributes reflected in traditions and cultures in each region.