At What Age Should a Child Start Fasting in Ramadan?
Question

What is the age at which children are obliged to fast? How can we encourage them to fast and pray in the mosque, especially Tarawih prayer? Are there any simple religious ideas which can be used to fill children’s spare time in Ramadan?
Praise be to Allah.When should children start fasting?
Fasting is not obligatory for young children , until they reach the age of adolescence. Prophet Muhammad (peace and blessings of Allah be upon him) said: “The pens have been lifted from three: from one who has lost his mind until he comes back to his senses, from one who is sleeping until he wakes up, and from a child until he reaches the age of adolescence.” (Narrated by Abu Dawud, 4399; classed as sahih by al-Albani in Sahih Abi Dawud) 
Nevertheless, children should be told to fast so that they can get used to it, and because the good deeds that they do will be recorded for them. 
The age at which parents should start to teach their children to fast is the age at which they are able to fast, which will vary according to each child’s physical makeup. Some scholars have defined this as being ten years of age. 
Al-Kharqi said: 
“When a child is ten years old and is able to fast, he should start to do so.” 
Ibn Qudamah said: 
“This means that he should be made to fast and told to do so. And he should be smacked if he does not do it, so as to train him and make him get used to it, just as he should be made to pray and told to do it. Among those who were of the view that a child should be told to fast when he becomes able to do it were ‘Ata, al-Hasan, Ibn Sirin, al-Zuhri, Qatadah and al-Shafi’i. 
Al-Awza’i said: If he is able to fast for three consecutive days without interruption and without becoming weak, then he should be made to fast Ramadan. Ishaq said: When (a child) reaches the age of twelve I think that he should be made to fast so that he gets used to it. 
The age of ten is more likely, because the Prophet (peace and blessings of Allah be upon him) enjoined smacking children for not praying at this age, and regarding fasting as being like prayer is better, because they are close to one another, and because they are both physical actions that are pillars of Islam. But fasting is harder, so attention should be paid to when the child becomes able to do it, because some may be able to pray but are not yet able to fast.” (Al-Mughni, 4/412) 
This is what the Companions of the Prophet (peace and blessings of Allah be upon him) did with their children; they would tell those who were able to fast to do so, and if one of them wept because of hunger, they would give him a toy to distract him, but it is not permissible to force them to fast if it will harm them in cases of physical weakness or sickness. 
Shaykh Ibn ‘Uthaymin said: 
“A young child should not be forced to fast until he has reached the age of adolescence, but he may be told to fast if he is able to do it, so that he may get used to it and it will be easier for him after he reaches puberty. The Sahabah (may Allah be pleased with them) – who are the best of this ummah – used to make their children fast when they were young.” (Majmu’ Fatawa al-Shaykh Ibn ‘Uthaymin, 19/28, 29) 
And the Shaykh (may Allah have mercy on him) was asked: 
My young son insists on fasting Ramadan even though fasting is harmful for him because he is so young and his health is not good. Should I use force with him to make him break his fast?
He replied: 
“If he is young and has not yet reached puberty, he is not obliged to fast, but if he is able to do it without hardship, then he should be told to do so. The Companions (may Allah be pleased with them) used to make their children fast, and if the younger ones cried they would give them toys to distract them. But if it is proven that it is harmful to him, then he should be stopped from fasting. If Allah has forbidden us to give youngsters their wealth if there is the fear that they may abuse it, then it is more appropriate that they be stopped from doing something if there is the fear of physical harm. But that should not be done by force, because that is not appropriate in raising children.” (Majmu’ Fatawa al-Shaykh Ibn ‘Uthaymin, 19/83) 
Ramadan fasting tips for children
The parents can encourage their children to fast by giving them a gift each day, or by exploiting the spirit of competition between them and their peers or those who are younger than them. They can encourage them to pray by taking them to pray in the mosques, especially if they go out with their father and pray in different mosques each day. They can also encourage them by rewarding them for that, whether that is by praising them or by taking them out on trips sometimes, or buying things that they like, etc. 
Unfortunately some fathers and mothers fall far short in encouraging their children, and there are even some who stop their children doing these acts of worship. Some of these fathers and mothers think that mercy and compassion mean not making their children fast or pray. This is completely mistaken according to both the Shar`i point of view and educational wisdom. 
Shaykh Muhammad ibn Salih al-‘Uthaymin (may Allah have mercy on him) said: 
“Allah has enjoined fasting upon every Muslim who is accountable, able to do it and not travelling. As for young children who have not yet reached the age of puberty, fasting is not obligatory for them, because the Prophet (peace and blessings of Allah be upon him) said: “The pen has been lifted from three” and he mentioned young children until they reach puberty. But the child’s guardian must tell him to fast if he reaches an age where he is able to do so, because that comes under the heading of training him to implement the pillars of Islam. We see some people leaving their children alone and not telling them to pray or fast, but this is wrong, and he (the parent) will be responsible for that before Allah. They say that they do not make their children fast out of kindness and compassion towards them, but in fact the one who is truly kind and compassionate towards his child is the one who trains him to acquire good characteristics and to do righteous deeds, not the one who refrains from disciplining and training him in a beneficial manner.” (Majmu’ Fatawa al-Shaykh Ibn ‘Uthaymin, 19/19, 20) 
How to fill children’s spare time in Ramadan 
The parents can fill their children’s time with reading Quran and memorizing a small portion each day, reading books that are suited to their level, letting them listen to tapes which combine useful content with fun, such as nashids, and bringing them video tapes that are useful for them. The “al-Majd for Children” channel does all of these things, and time can be set aside each day for children to watch it and benefit from it. 
We would like to express our appreciation for our sister’s concern about her children’s upbringing. This indicates that there is still goodness in Muslim families. But many people do not do well in bringing out their children’s intellectual and physical potential, and they become lazy and depend on others. They also do not care about encouraging them to do acts of worship such as fasting and praying, so many children grow up in this manner and their hearts are devoid of worship after they grow older, and it becomes difficult for their parents to direct them and advise them, whereas if they had paid attention to this matter from the outset, they would not have ended up regretting it in the end. 
We ask Allah to help us to raise our children well, to make them love worship, and to help us to fulfil our duties towards them. 
And Allah knows best.