Boarding is always controversial on here. My DS2 boarded from 7 years old. Before he and I looked at the school I thought parents who sent children off to boarding school were monsters especially little children. Although the kindest funniest easiest to work with friend/work colleague adored by all went to boarding school from 7 but I still had many of the misconceptions that are detailed by those above.
We looked at boarding through necessity. We knew we wanted DS2 prepared for CE and but there were no prep schools within sensible driving distance (we're rural) so we planned to move house for yr 5 to get him into a day prep (we weren't in a position to move at that time). My DS was at a tiny roses round the door/thatched roof/accessed through an orchard primary school the sort of place many in cities dream their DC's could attend. But for him it was not working he is exceedingly bright but with a particular ability at math (IQ score over 140) basically not only was he better at math than his classmates he was also better at math than all the other pupils and the staff (all four of them), who frequently made errors which he felt duty bound to point out. He was given his own text book to do at home but the staff couldn't tell him if the answers were correct because they couldn't do the questions. After some discussion we were told by the governors that they had neither "the time interest or money" to offer him more support as statistically the chances of another one coming along with his ability in the next 20 years were small. I then approached a marginally larger primary, one of the counties top performing school they also when pushed were going to do little more. My DS was bored stiff, he always had friends or friends with siblings at boarding prep so had none of the misconceptions/prejudices that many have so at 7 years old he off his own back suggested he went to a boarding school.
I'd be the first to admit I went to look at it very reluctantly, to say the least, but what I saw was happy relaxed fresh faced tanned children, who were being allowed to be what they were, children. I won't bore you with the differences in curriculum the extra curricular activities etc because I know some think their primary school offers the same thing, but I genuinely felt that the lessons and math in particular with it's specialised teachers and classrooms, removed from the the restrictions of Sats and the national curriculum would be more challenging and interesting for him. Unable to find this in any day school (state or private) within sensible doable driving we felt we had little choice.
Ten years later we're still full boarding, at various times in his life my DS has been offered viable day/flexi boarding options and still he stays. I'm not going to pretend he's been happy all the time but can any child at any school claim every day has been happy I doubt it.
He's not institutionalised by any stretch of the imagination in fact far from it, he is significantly more independent than friends who don't board and has been effortlessly able to shift for himself from an early age, he's exceedingly adaptable, a common trait amongst boarders, can very quickly read a situation and work out what's expected of him, he's learnt to live, sleep, eat, play and work along side a group of people who are all different from him some who he likes, some who he doesn't, a non team sports player and a natural non team player he's learnt how to work in a team. He lives with the distracting, the irritating, the funny, the serious, the difficult, the untidy, the hard working the lazy and yet manages to cope and adjust effortlessly. A skill which I believe will stand him in good stead when he goes out to work. He may not be able to boil an egg but he has learnt many other practical skills which non boarders don't have.
He also doesn't need his spare time filled with activities in fact he loves to be bored, nor does he need a rigid routine he would tell you the joy of being at home is that you're with your family and the chance to sit and do nothing in an unplanned day.
Boarding is not right for all children or parents but for many for it is a as I so frequently say a positive life enhancing experience.