Experts and helpers were on hand for the challenge, which centred on the disappearance of a secret formula which would revolutionise treatments for acne. One table comprised five final-year pupils from Airyhall primary school.
10.45: A bad start. Craig and Nicky have filled two A4 sheets in an attempt to solve the coded message. They opt for an extra clue costing them 50 points, but remain baffled.
10.50: Lyndsay, Graham and Cara have managed to separate two of the three component parts of a mixture properly. They have sand and sawdust, but where is the salt?
10.55: The team wants to move on to the next two challenges, but someone's mum has gone off with the instructions in her handbag.
10.56: Craig starts on a poster design while the others construct a paper stool that will bear the weight of the smallest team member and create a balloon parachute which will land on a marked target (with accuracy points ranging from 10 to 50) when launched from a balcony.
11.15: Craig, the smallest, tries to balance on a "stool" made of tightly wrapped magazine tubes. He removes his shoes steps up . . . and limps back to his poster.
11.20: The rest of the team land the balloon-and-weight on the target's outer score of ten. They get carried away and test it to destruction. Pop!
11.25: The new balloon is weighted with plasticine and treated with respect. In a quiet corner Nicky struggles with the dreaded code.
11.35: Cara's tummy is rumbling and the boys "feel like we've been here all day".
11.40: The balloon lands consistently on scores of 40 and 50. With a great shout, Nicky cracks the code. It is as if a light has been switched on somewhere. Stomachs are forgotten. Lyndsay strengthens the magazines, Cara matches fingerprints, Graham tests the balloon while Craig does likewise with the stool.
12.15: The five are coaxed away to lunch.
13.00: Craig is hauled away from poster design for the official test of the paper stool, but even with an adult on either flank, Cara propping up his back, and the rest fanned out like rig anchors from the construction's base it does not pass muster. At least it meets the height requirement.
13.15: The balloon scores 40, and they come first. But they wanted perfection. "Why didn't it land on the 50?" 13.25: The finishing touches are interrupted by a wail from a nearby table. Someone misread the instructions and designed a poster for washing-machine powder instead of spot-removing cream.
13.30: No such problem at Fiddley Five's table where the team has made Craig's work of art the centrepiece of the highs and lows of the day's labours.
14.15: After judging the winners were: The Amazing Animals (St Margaret's, Aberdeen), followed by The Challengers (another Airyhall team) and IQ 100 (Ordiquhill primary, near Banff). But wait, there is a special team prize for the best poster and it goes to the Fiddley Five. Coloured pen sets and enormous grins all round.
14.30: Five head for home. No doubt a future science lesson will show how to retrieve salt crystals from a soluble solution.