There is a babble of chatter in the gym hall as ideas are pitched and rejected until the light bulb moment.
Almost a hundred pupils are paired up to take part in the Junior Engineers for Britain K'Nex Challenge at Strathburn Primary at Inverurie. With their boxes of K'Nex sitting on the floor between them, the Strathburn pupils are chatting through their plans with great animation.
They have been given their design brief and told what they must build and the problems they must resolve during construction. After a two-minute discussion, building is underway. The winning pair will go through to a regional final, and from there to a national final later this year.
If you have never seen eight-year-olds battle against the clock to design a piece of civil engineering in miniature, then this is something of an eye opener. Their speed and creativity is amazing - their sense of purposeful calm would put adults five times their age to shame.
They have just 40 minutes to get the job done, but there are no prima donna sulks or tantrums, no raised voices or Apprentice-style looks of silent frustration. These Aberdeenshire children are just getting on with it and the work they produce is very impressive.
The event is organised by TechFest-SetPoint, a charity set up to promote science, technology, engineering and maths; it is sponsored by the Wood Group and Talisman Energy. More than 6,000 children will take part in the North East and Tayside alone as part of this national competition.
The P4s take part in a morning session and the P5s are in the afternoon group. Winners of this school's morning session are Katherine Atkinson, eight, and Alina Tuzova, seven, who came to the school from Russia just a few years ago.
Katherine reveals the secret of their winning partnership: "We had a handshake and we kept saying to ourselves `we can do it, we can do it' all the time," she says, sitting with the certificates they've been given to mark their success.
"I want to be an engineer like my dad," says Katherine. "He does the blueprints for boats for the oil rigs." Alina intends to follow suit: "I want to do the same as Katherine."
The girls are among thousands of seven to 11-year-olds taking part from 88 schools across Aberdeen and Aberdeenshire between now and Easter. Many more schools here and in Tayside have still to take this specific challenge - so revealing their task is not an option.
Strathburn headteacher Harry Burnett says the competition challenges the children on several levels: "They have a design remit and they have to work together, use their imagination, use their thinking and design skills to come up with something that's going to work."
He says the pupils start to think creatively about design from the outset: "K'Nex is part of what we have been doing for many years. We have lots of different construction activities throughout the school and we like to think that we are into designing from nursery right through. In fact, the littlest ones are sometimes the most imaginative.
"It gives an external evaluation in some ways because someone comes in and gives the children an opportunity to use their skills, and it's quite fascinating to see how the children will respond to that. Usually we have children that go on from here and take up the challenge onto the next round."
The winners of the afternoon session are announced as the overall winners at Strathburn: nine-year-olds Kristoffer Booth and Callum Stuart will now go through to the next stage of the competition at the end of May.
As they build their structure, they take the excitement and the pressure in their stride. Kristoffer sums it up: "It's fun. Everybody in the world should do this."
`THEY JUST AMAZE US'
TechFest-SetPoint presenter and judge Julie Hutton takes children through the rules of the competition, which is underway in Aberdeenshire schools and will continue across Aberdeen and Tayside until Easter.
"The children are really excited," says Mrs Hutton. "They are totally enthusiastic and it's just lovely to catch children at this age and see how their minds are working. And hopefully this is encouraging them to think along science, mathematical and engineering lines in the future."
She says it's important that the design meets all the objectives set: "I am looking for two people who work very well together and co-operate well. I am looking for two people with uniqueness in their ideas, and I am looking for them to meet all the other criteria that are part of the challenge."
Louise McGregor, STEM co-ordinator from TechFest-StemPoint, who organises the overall event, says she never ceases to be amazed by the children's ingenuity. "They just amaze us every year," she comments. "Young Engineers come up with such a fantastic challenge and the children always produce such terrific models."
One of the Strathburn teachers supervising pupils at the competition says the event captivates children. "They absolutely love it," says P5 teacher Jackie Fraser. "They all seem to be engaged with it. Its hands-on and very good for collaborative learning and working together."