Okay, not Helensburgh, with the gift of Google I have found this here article, Lomond school, mentioned at the end as somewhere not kilty, is the one in Helensburgh:
Kilts were often worn to School. Boys wore kilts to both state and private schools. But the cnventions varied at these different schools. State primary schools catered for children up to about 12 years of age and secondary state schools continued their education up to the official leaving age of 15 (up to 1950 and 16 thereafter) or up to 18 for those going on to university. Private schools (fee paying) were either day schools or boarding schools and covered the age range of 5 to 12 (preparatory schools) and secondary education up to age 18.
Until the 1960's, normal uniform at state schools was short trousers in primary and in secondary schools up to the 2nd or 3rd years (ages 14 or 15) with long trousers thereafter. The kilt was always a permitted alternative for both primary and secondary state school boys. Numbers choosing to wear a kilt varied by age, by area, and by school. In some areas and in some schools, more than half the boys would be wearing kilts and in others none at all. Up until about 1960, the country primary schools, particularly in the Highlands and South Western Scotland had the greatest number of kilted boys. For secondary schools it was the cities of Inverness, Aberdeen, Glasgow and Edinburgh where the kilt was most often seen in a classroom.
In a few fee paying day schools a kilt was the official school uniform. More often it was an alternative to short trousers. One or two schools insisted that all boys, even seniors aged 18, wore either short trousers which were regarded as juvenile by the older boys or the kilt, which was much preferred.
At boarding schools, kilts were THE uniform for Sundays, parades, and exeats of all types, including sports fixtures with other schools. Some schools stressed Scottish Country Dancing and of course the kilt was required wear for the lessons. Out of 14 prep schools surveyed a few years ago, 8 still have the kilt as prescribed uniform for the above activities and in 3 it is optional. Three schools do not wear the kilt at all.
Out of 13 Scottish boarding schools polled in 1989, kilts were still compulsory in 9 of these and optional in one. If they didn't have a tartan of their own boys usually wore Hunting Stewart. At some schools there was also a cadet corps and of course kilts were worn there. These were usually army kilts and were worn for parades, travel to camp, inspections etc. Travel to and from school ws usually in kilt but the boys from England were allowed to dress in other garments, in one case plus fours. By the 1980s, the kilt was only commonly worn at boarding and preparatory schools in Scotland.
Boys at the following nine boarding schools were required to wear the kilt.
Dollar Academy: Boarders were required to wear the kilt on Sundays for church and on school social occasions such as dances and parties.
Fettes and Glenalmond: On formal occasions boys wore the kilt with a waistcoat and jacket of the registered college tweed. The kilt could be of any personal tartan but all boys in the College are entitled, if they wish, to wear the Hunting Murray tartan.
Kiel: Boys wore a white shirt, school tie, school blazer and kilt as the number 1 uniform. It is worn on Sundays and for special occasions as well as for outings.
Loretto: Sunday garb is white shirt and tie, lovat tweed jacket and the kilt.
Merchiston Castle: The kilt was worn on Sundays and on formal occasions.
Rannoch: On Sundays and special occasions boys dressed is the kilt and Rannoch Green jacket. The dress list for Formal Wear includes, 1 kilt (tartan of own choice), 1 kilt jacket, 1 sporran, 2 pairs of school stockings (Rannoch Green), 2 white shirts, 1 school tie, and 1 pair of black lacing shoes.
Strathallan: Boarders were required to wear the kilt on Sundays for church and on school social occasions such as dances and parties.
Queen Victoria School Dunblane: The traditional ceremonial uniform of glengarry, scarlet tunic and kilt is worn for church and special occasions. In 1966 walking out dress was changed from battledress to highland tweed jacket, pullover and kilt. Highland dancing is still part of the curriculum.
The kilt was optional at:
Edinburgh Academy: Optional formal dress was kilt with appropriate tweed jacket, plain lovat coloured stockings, lacing black shoes, white shirt and Academy tie. A plain grey V-neck pullover and Glengarry or Balmoral hat are further options.
The following three schools did not wear the kilt: Fort Augustus Abbey, Gordonstoun, and Morrison's Academy in Crieff. This was the situation in 1988. HBC has seen earlier photographs from Goronstoun, for example, with all the boys turned out in kilts.
The following eight preparatory schools wore the kilt:
Ardvreck, and Crawfordton House: The kilt outfit was worn on Sundays and for outings.
Blairmore, and Cargilfield: On formal occasions boys wore kilts.
Lathallan: Children wear the kilt for church on Sundays and for all other important school events. The tartan is of their own choice.
Loretto Preparatory: The kilt is formal dress on Sundays and special occasions except in the summer term when red blazers and white shorts are worn.
New Park: On formal occasions boys wear kilts.
Queen Victoria (Preparatory School): See above.
The kilt is optional in the following three schools:
Clifton Hall. On Sundays in the Autumn and Spring terms most boys wear the kilt.
Edinburgh Academy and Fettes: The kilt with tweed jacket may be worn for special occasions by boys in the prep school section of these senior schools.
Aberdour Preparatory School: This prep school is not Scottish, but located at Banstead, Surrey. Until 1987, the headmaster allowed any Scottish boy to wear the kilt if they so desired. At one stage, there were as many as 35 kilted boys. They wore the kilt every day, not just on Sundays as is the case in the other prep schools. The kilts belonged to the headmaster at the time, Mr Grange, and were eventually gifted to the Scottish Tartans Society where they are having another useful life being lent out to any boy who wants one and agrees to wear it.
The kilt was not worn in the following three schools: Belhaven Hill, Lomond, and St Mary's
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