What is the appropriate age to teach children sex education?
Question

                What is the appropriate age to give children sex education?
Praise be to Allah.
    Firstly: 
It 
    is essential to know that children are a responsibility for parents, as it 
    says in the hadith that was narrated from ‘Abdullah ibn ‘Umar who said: I 
    heard the Messenger of Allah (blessings and peace of Allah be upon him) say:
    

    “Each of you is a shepherd and each of you is responsible for his flock. The 
    ruler is a shepherd and is responsible for his flock. A man is the shepherd 
    of his household and is responsible for his flock. A woman is the shepherd 
    of her husband’s house and is responsible for her flock.”

    Narrated by al-Bukhaari (853) and Muslim (1829) 

    Part of that responsibility that the parents have towards their children is 
    protecting them from everything that may lead to corrupting them or have a 
    negative impact on their morals. 

    Secondly: 
It 
    is well-known that teaching what is called sex education in the West has 
    become an obsession and madness, and it has become their main concern. 
    Separate classes have been allocated for it in the schools, and there are 
    programmes on television, and seminars and conferences are held concerning 
    it. Unfortunately many Muslims have been affected by this culture, 
    especially those who have been deceived by their culture and civilization. 

    Undoubtedly teaching children about sex and related matters at an early 
    stage in their lives leads to many negative consequences.
We 
    have discussed this previously; please see the answer to question no.
    113970 

    Thirdly: 
It 
    should be noted that teaching children – male or female – the Islamic 
    etiquette having to do with covering the ‘awrah, controlling the gaze and 
    asking permission before entering private spaces should begin when they are 
    very small, from an early age, and when they reach the age of discernment, 
    and before they reach the age of puberty. There is evidence in the 
    revelation which clearly speaks of that, including the following: 

    1.Allah, may He be 
    exalted, says (interpretation of the meaning):

    “O you who 
    believe! Let your legal slaves and slave-girls, and those among you who have 
    not come to the age of puberty ask your permission (before they come to your 
    presence) on three occasions; before Fajr (morning) prayer, and while you 
    put off your clothes for the noonday (rest), and after the Isha (late-night) 
    prayer. (These) three times are of privacy for you, other than these times 
    there is no sin on you or on them to move about, attending (helping) you 
    each other. Thus Allah makes clear the Ayat (the Verses of this Quran, 
    showing proofs for the legal aspects of permission for visits, etc.) to you. 
    And Allah is All-Knowing, All-Wise”
    

    [an-Noor 24:58]. 

    Ibn Katheer (may Allah have mercy on him) said: Here Allah, may He be 
    exalted, instructs the Muslims that their servants and slaves, and their 
    children who have not yet reached the age of puberty, should ask permission 
    before entering rooms in three situations, the first of which is before Fajr 
    prayer, because at that time people are usually sleeping in their beds. 
“and 
    while you put off your clothes for the noonday (rest)” 
    that is, at the time of the siesta or midday nap, because a person may take 
    off his clothes at that time with his wife. 
“and 
    after the Isha (late-night) prayer” 
    because this is the time of sleep. 
So 
    servants and children should be instructed not to enter rooms suddenly at 
    these times, because of the fear that the man may be in an intimate 
    situation with his wife, and so on. 

    Tafseer Ibn Katheer 
    (6/82) 

    When children reach the age of puberty, then they should seek permission to 
    enter at all times, as Allah, may He be exalted, says (interpretation of the 
    meaning):

    “And when the children among you come to puberty, then let 
    them (also) ask for permission, as those senior to them (in age). Thus Allah 
    makes clear His Ayat (Commandments and legal obligations) for you. And Allah 
    is All-Knowing, All-Wise”

    [an-Noor 24:52]

    2.It was narrated 
    from ‘Amr ibn Shu‘ayb, from his father, that his grandfather said: The 
    Messenger of Allah (blessings and peace of Allah be upon him) said: 
    “Instruct your children to pray when they are seven years old, and smack 
    them if they do not do it when they are ten years old, and separate them in 
    their beds.”

    Narrated by Abu Dawood (495); classed as saheeh by al-Albaani in Saheeh 
    Abi Dawood. 

    Shaykh Muhammad Shams al-Haqq al-‘Azeemabaadi (may Allah have mercy on him) 
    said: 

    Al-Mannaawi said in Fath al-Qadeer Sharh al-Jaami‘ as-Sagheer: That 
    is, separate your children in the beds in which they sleep when they reach 
    the age of ten, as a precaution against provocation of desire, even in the 
    case of sisters. 

    At-Teebi said: Allah mentioned together the ideas of instructing them to 
    pray and separating them in their beds in childhood, so as to discipline 
    them and obey all the commands of Allah, and to teach them, to show them 
    proper etiquette with people, and to teach them not to put themselves in 
    suspicious situations and to keep away from sin. 

    ‘Awn al-Ma‘bood 
    (2/115) 

    This advice and guidance from this verse has to do with protecting and 
    concealing the ‘awrah and avoiding provocation of desire which begins, as we 
    have seen, in the tenth year, which is the age at which most children reach 
    discernment. 

    When puberty approaches, children should be taught the signs of puberty and 
    the characteristics which distinguish men from women, and the types of 
    discharge that may be emitted from the front passage of both sexes. They 
    should also be taught the rulings on wudoo’ and ghusl, paying attention to 
    the phrases used in teaching and ensuring that it is taught according to 
    what the child needs to know. 

    For information on the signs of puberty, please see the answers to questions 
    no. 70425 and 20475 

    There are two very important matters which begin at a very early age – 
    around the age of three years – that have a basic connection to the issue of 
    sex education. They are: 

    1.The necessity for 
    the boy or girl to be able to distinguish between male and female. Confusion 
    between them at that early age could lead to troubles and confusion in 
    concepts, characteristics and actions, in both sexes. Hence it is essential 
    to make a boy understand that he cannot wear his sister’s clothes, or wear 
    earrings or bracelets, because these are for females, not for males. By the 
    same token, a girl should be told similar things about her brother’s actions 
    and characteristics.

    2.Teaching children 
    that the ‘awrah is private, and that it should not be uncovered for anyone. 
    Teaching them this, and bringing them up with it, is a way of instilling in 
    them the characteristics of chastity and modesty, and will help prevent 
    perverts from transgressing against them. 
    

    Fourthly: 

    With regard to the issue of sex education having to do with intercourse, or 
    what happens between spouses in general, this should come when there is a 
    need for it, such as when marriage is approaching, or when he is mature 
    enough to understand some issues of fiqh, such as the rulings on zina 
    (fornication or adultery) and the like, which have to do with intercourse 
    and ‘awrahs. 
It 
    should be noted that what is needed of that knowledge is basically something 
    that is natural and instinctive in the first place, and what you need to 
    point out must be taught to children gradually, in accordance with the 
    stages of their development, by means of lessons of fiqh, study circles and 
    classes in school. We should be conservative in the words and phrases we 
    use, and attention must be paid to the appropriate ages and stages to 
    discuss this topic. We must also warn against the promiscuous practices of 
    the disbelievers and contrast them with the beauty of Islam, with regard to 
    urging Muslims to cover up and be modest, and to guard their chastity and 
    avoid that which is haraam. 
We 
    advise you to read the book Ya Bunayya laqad Asbahta Rajulan by 
    Shaykh Muhammad ibn ‘Abdullah ad-Duwaysh, which explains Islamic ways of 
    dealing with desire in children. 

    And Allah knows best.