When we moved here my son was 13. I thought it highly unfair to put him in a Spanish school at that age (we live inland ,so no international schools). We asked him what he wanted to do, we would either stay in the UK until he had finished his education, or he could go to boarding school in the UK, He chose boarding school and has done very well. He has just finished a degree and walked straight into a graduate job with airbus. If he had not settled at boarding school we would have returned to the UK until his education had finished!!
I think education is very important and it is the parents duty to help provide it. I do realise that boarding school is expensive and not everyone can afford it, and yes we struggled!!
There are a few Brit kids in our village and my OH offered to teach them English (free) The parents were not interested and questioned why their children needed it in Spain!! Since then a couple of the families have returned to the UK with children that can hardly read or write English! What future do these children have?? The narrow mindedness of their parents has probably destined them to a life of poorly paid jobs, if they manage to get one at all!!