Indeed, the process might have been quite traumatic for the natives. On the flip side, the aliens might have had the best of intentions, alas executed with significant flaws. It so happens that boarding schools are (were?) a major tradition in the alien British culture.
> Boarding schools in Britain started in medieval times when boys were sent to be educated at a monastery or noble household, where a lone literate cleric could be found. In the 12th century, the Pope ordered all Benedictine monasteries such as Westminster to provide charity schools, and many public schools started when such schools attracted paying students. These public schools reflected the collegiate universities of Oxford and Cambridge, as in many ways they still do, and were accordingly staffed almost entirely by clergymen until the 19th century. Private tuition at home remained the norm for aristocratic families, and for girls in particular, but after the 16th century, it was increasingly accepted that adolescents of any rank might best be educated collectively. The institution has thus adapted itself to changing social circumstances over 1,000 years.
> It so happens that boarding schools are (were?) a major tradition in the alien British culture.
A very harmful tradition, IMO, even in elite schools like Eton.
In my hypothetical, the aliens consider a hive-mind as an ideal as it would wipe out all wars and conflict, and improve collaboration (imagine if all 20th century mathematicians had a Erdős number of 1, and all his insights retained after the death of his biological unit). All this progress would come at the cost of getting rid of "individualism" - a very backward, romanticized, but inefficient notion that is clearly outweighed by the benefits (in the aliens mind).
https://en.wikipedia.org/wiki/Boarding_school#United_Kingdom
> Boarding schools in Britain started in medieval times when boys were sent to be educated at a monastery or noble household, where a lone literate cleric could be found. In the 12th century, the Pope ordered all Benedictine monasteries such as Westminster to provide charity schools, and many public schools started when such schools attracted paying students. These public schools reflected the collegiate universities of Oxford and Cambridge, as in many ways they still do, and were accordingly staffed almost entirely by clergymen until the 19th century. Private tuition at home remained the norm for aristocratic families, and for girls in particular, but after the 16th century, it was increasingly accepted that adolescents of any rank might best be educated collectively. The institution has thus adapted itself to changing social circumstances over 1,000 years.