It is a pupil's dream and a teacher's nightmare - a summer's day out on a beach clean-up when someone shouts: "We've found a bomb."
The P6s-7s from St Fergus School were working on their transition project, "Around our Coast", to help prepare the older children for moving to the big school. The beachcombers were also making artwork with what had been washed ashore to show at the Peterhead Heritage Fair to celebrate Homecoming.
But the stroll on the shore shifted up a gear when one of the children stumbled on something submerged in the sand. "One of the groups was looking for shells and someone tripped over this thing and started digging round it," says Ashley Thomas, an energetic 12-year-old.
"It was a big metal sphere and it looked heavy," explains the young lad who has now left the cosy familiarity of his village school for Peterhead Academy, a few miles further south. This village also gives its name to the St Fergus Gas Terminal, which processes fuel brought ashore from the North Sea, and has close ties with the school.
One of Ashley's teachers, Claire Grugeon, was with them: "They were roaring across the beach: `We've found a bomb' - there was great excitement." She and colleague Avril Sutherland retreated with the children into the sand dunes, leaving the experts to investigate. "It turned out it was one of these old buoys," says Mrs Sutherland, who job- shares with Mrs Grugeon. "But there was great excitement before it was removed."
On the last day of primary school, parents and grandparents, with wee brothers and sisters crowded into the school hall. It was a hot day, but even babies in their buggies were well behaved, as Ashley and his friends reconstructed dramas they had uncovered from their coastal heritage.
And what a past it turned out to be - smugglers' tunnels down to the sea, shipwrecks, pirates, body-snatchers, a tragic girlfriend dashed on the rocks! The pupils tell these stories with the kind of animated eloquence usually reserved for the extra-curricular. Dean Fairbrother, 12, says one visit to the nearby Pirates Graveyard was particularly powerful because it's where some of their ancestors are laid to rest.
"Scarlet fever was a really common disease. A father and five children who died of it, but the mother lived until she was 95," he says.
"Round about our coastline there's been lots of smuggling and pirates and everything like that," says Ashley. "Down in Botany Bay, there was massive smuggling going on and it was named after Botany Bay in Australia because of all the smuggling. They were smuggling loads of things like lard, salt, apples."
"And bodies," says 10-year-old Iona Helyer, sitting next to him. "They were stealing bodies from the graveyard - digging them up and selling them for tests."
The children explored miles of their coastline, visiting lighthouses and beaches, exploring rock pools, investigating dune formations and endangered species at the Loch of Strathbeg Nature Reserve. They also went to Peterhead Academy and met the P7s from the other eight feeder primaries before each school embarked on a dedicated week of Around Our Coast activity.
Mrs Grugeon and Mrs Sutherland decided to devote the whole term to their coastal studies: "We've got a fantastic area and it was just such a Curriculum for Excellence-led project because it was all so active, and every week we had different things for them to do," says Mrs Grugeon.
Headteacher Ruth Mackenzie played a key role in co-ordinating the project: "The secondary school will pick up on some of the Curriculum for Excellence outcomes that we have covered and will take them further - to level 3 probably," she says. "So our P7s, now they're up at the academy, have a short spell to work on the project they have just completed."
Mrs Sutherland says: "There was loads of language work, imaginative and factual writing because they had to make PowerPoint presentations, fact files, leaflets and posters."
"It was a really exciting project for us - the children loved it and they got so much out of it being in their own environment. A lot of them had never gone to these places and they live right beside them," adds Mrs Grugeon. "The next few evenings, they were going down and playing there. Their parents were really pleased to see them using their own environment."
A few weeks later, Peterhead held its Heritage Fair and the power and fascination of the past was evident. Visitors were scrutinising old photographs and reading children's descriptions - discovering new things about their own villages from the research.
Central School was the venue - one of 12 held across Aberdeenshire, involving schools and communities. The idea, taken from a Canadian model, is that schools, museums, artists and performers and local heritage groups can become actively involved in celebrating their unique history and traditions.
The Peterhead hall was packed with stalls, displaying everything from Grampian Police memorabilia of ancient truncheons to sepia photographs assembled by the local family history society.
On the stage, two men were singing a sea shanty about the whaling industry which once flourished in this community. They were being watched by children in Victorian costume, who were about to perform a musical production based on their own historical research.
The primary pupils' work was on show too and artist Willie Moulding, who worked alongside them, gave a tour, pointing out the shells, driftwood and rubbish they collected on the beach which had been used to create colourful displays with titles like "Funky Junk."
"Primary 7 is a great age to work with. They are still playful - they don't seem to have any of the hang-ups that they get in the academy, where they are a bit worried about everyone and wondering what people think of them, and growing up and trying to be cool," he says.
"In P7, they are at the top of their game because they're at the top of the school. If you introduce something to them to draw, they'll go `OK' and draw it. But if you do that with a second year, it's `Oh I can't draw!' That kicks in at the academy when they are a bit more faceless in the crowd."
Mr Moulding's role was about boosting confidence in their art and themselves: "The coast project is a transition programme to ease the move from P7 up to first year, and it works; it definitely gives them confidence in their art as well."
Recently retired primary teacher Margie Davidson volunteered to go into schools to help with the project: "I'm a fisher myself - the fishing's my heritage so I do a lot through the family history society and give talks to different clubs," she said, as we toured the displays.
"The children are fascinated because when I was doing supply in Buchanhaven, we did a project on themselves and their history linked to the old pictures of Buchanhaven I have.
"They came in, fascinated - `Oh my granny can remember this' - and they made a super job of that work because they discovered their own heritage was part of what we were talking about."
Two elderly ladies in rain-mates and waterproof coats had stopped at the old fishing family photographs and spotted someone they knew. "She was a great friend to me," said one. Her friend nudged her: "Look, this is the top of High Street, mind in Buchanhaven, and this is Dogger Jock's crowd down at the bottom of Harbour Street."
"These are fisher folk you see," Margie whispered, and we tiptoed away, leaving them on their delighted detour down memory lane.
In the main hall, the audience had been watching a performance of Lottie - a musical production based on the true story of a girl born in Peterhead Poorhouse in 1878.
It's unusual for the cast to be so emotionally attached to the heroine, but the performers did their own research and discovered Lottie's story themselves. The cast included primary pupils through to college students and they gave polished performances.
Lottie's story came to light in the Peterhead Poorhouse governor's journal, and the Aberdeenshire performers followed her life's struggle in records across the country. She died in another poorhouse, just 30 years old.
They were from the Rhona Mitchell School of Drama and were pupils at schools and colleges across the north east. Rhona Mitchell has a passion for history: "I have a tremendous interest in it," she said, as the cast relaxed afterwards. "Sometimes I feel sorry for them because they say: `Are we doing another old piece?' - but they still get drawn in."
It's a family effort - Rhona's daughters Olivia, Rosalind and Imogen were in the cast and Rosalind played Lottie.
Another performer, Claire Gauld, 19, talked about the research and how the archives helped with the scripting. "I looked at the governor's journal," says the former Meldrum Academy pupil, now studying primary teaching.
"I also looked at the plans of the poorhouse so I could see what it was like to actually be inside one. Everyone would say, `What's the update on Lottie?', and we'd find out another amazing story about her."
There was adult input too - playwright Charles Barron helped and archivist Ruaraidh Wishart from Aberdeen City Archives encouraged them as they traced Lottie's life in church and hospital records.
In a final coup, they tracked down Lottie's great great niece, who accepted their invitation to join them for the opening performance. "We're a lot more attached to this story because we know it was a real person and a real story," said Claire. "And that we traced it."