Waiting parents at Fraserburgh Academy are impressed when they enquire about the young visitors arriving in their pale-blue sweaters.
"Oh lovely, they're from Gordonstoun," says one mum, glimpsing the teenagers as they make their way to the hall.
Their hosts give them a royal welcome. The last British royals at Gordonstoun School were Peter and Zara Phillips, the Queen's grandchildren, some time ago.
This visit marks the start of a unique collaboration on values education between one of the most famous private schools in the world and a Scottish state school. In the coming months, pupils will hold seminars on leadership, visit the international leadership centre Columba 1400 on Skye and work aboard Gordonstoun's training yacht, "Ocean Spirit of Moray".
On the day I visited, Fraserburgh Academy's S2s were leading a session on peer support training for Gordonstoun pupils; the following week, Gordonstoun was to host a training session by ChildLine.
This project has been a year in planning, with meetings involving Aberdeenshire Council's director of education Bruce Robertson, senior staff from the schools and trustees from the Gordon Cook Foundation which is backing the initiative.
Acting rector at Fraserburgh Academy, John Noble said the schools had already found areas of shared interest: "We have recently revised our school values, and at assemblies we have been speaking about integrity, perseverance, focus and service - which are some of ours.
"Gordonstoun has values which are not the same, but there is a lot of overlap - in our strategies for delivering values education too. So once we started talking, we found a lot of common ground. It's been a productive partnership, and both schools are enthusiastic."
Mr Noble said he hoped friendships would develop from the association: "It's not something we are going to force. If it happens, that will be a bonus."
After his introductory talk, pupils made their way to the canteen for a break before the training session. Over coffee, the Gordonstoun staff talked about their hopes for the partnership. Gordonstoun is in remote countryside six miles from Elgin, and it has links with state schools for sport, music, drama and dance. But the partnership with Fraserburgh Academy is a one-off.
Paddy Innes-Hill, director of international and spiritual citizenship at Gordonstoun, with responsibilities as deputy head for pastoral care as a multi-faith chaplain, said: "I think what is unique about this particular link is that it's formalised, and it's a genuinely full sharing of ideas from both schools. We're developing the ideas together, which is really exciting."
He said there were pupils at both schools from similar backgrounds in the north east of Scotland: "We have a number from fishing backgrounds in Lossiemouth and Hopeman, Burghead, Buckie and Banff."
Gordonstoun has changed since the days of cold showers and gruelling cross-country runs when Prince Charles was there. But the values of founder Kurt Hahn are maintained in the Four Pillars of a Gordonstoun education - internationalism, adventure for self-development, service to the community and responsibility.
"The big thing is going into the hills on expeditions or out on the yacht on sail training voyages. There is an element of toughness there, but the service element is huge," said Mr Innes-Hill.
Fraserburgh Academy sent students to the leadership academy at Columba 1400 just over a year ago and, since then, those pupils have been passing on what they learned to pupils and to teachers at an in-service day and in after-school sessions.
Depute rector Pauline Buchan said: "It's about looking at yourself as a leader and looking at your inner values and how they come out in leadership."
Pupils in each year peer-support the year below: "It adds another layer of support for pupils," she said. "It's the low-level issues where pupils can mediate between each other, and the pupils are trained in what is confidential and what they can pass on to staff."
Fourteen-year-old Ian Parker lives near Hopeman and has just started as a day pupil at Gordonstoun: "It's good that schools are getting together and that people are helping new people in school," he said.
Laura Scott, in second-year at Fraserburgh Academy, said she had met Gordonstoun pupils before at badminton matches: "I think it's a good opportunity for us to pass down what we have learned and for them to see what we've been doing here."