Girls should be advised not to shave. Hair will not grow back darker or thicker but shaving will result in a rough 'whisker' for a few days which will not appeal to the girl. If she is very self-conscious about hair growth, refer to a doctor or a licensed beautician. Menstruation is a major source of curiosity for both boys and girls. The list goes on.
Wet dreams are a source of concern for boys.
Some boys who do not know about ejaculation may try to stop the semen from coming out. This can result in an inflammation of the testicles - another reason to talk. During ejaculation, including during wet dreams, only one teaspoon of semen comes out. Although there are about two hundred to five hundred million sperm in this teaspoon, it does not leave a large stain or mark. The fluid is white and thick.