Opinion is sharply divided on the musical merits of the bagpipes, even in their homeland of Scotland.
To some they are a sublime and versatile instrument, capable of stirring the blood to martial ardour one minute and piercing the heart with shafts of melody the next. To others they are noisy, tuneless and sentimental.
But there is no debate about the sound produced by the electronic bagpipes constructed during the Madlab Workshop by pupils at Southmuir Primary, Kirriemuir: "It drove my Mum up the wall," says Claire the next day.
The little squares of circuit-board are peppered with stripy resistors and orange capacitors. The children build and take them home with them, to unsuspecting parents to whom the small instruments no doubt look innocuous enough.
But the climax of the one-and-a-half hour workshop, which saw 20 of the newly-built devices emitting their own wheezy and startlingly loud notes when played with gusto by their eager constructors, is nothing short of unforgettable.
"It sounded," says class teacher Cameron Watt, "like a practice session of the local pipe band."
But whereas the band might belt out Amazing Grace, the children favoured Jingle Bells and the theme tune from Teletubbies. "I can play Mary had a Little Lamb," says Stacey. "I can play two tunes that really annoy my Mum and Dad," says Iain.
Any device that annoys adults while being educational is bound to please children, but it turns out this is not the most appealing aspect of the workshop.
"My favourite part was the soldering," says Steven. "I loved the soldering" agrees Sanna. "Soldering was cool," says Aimi.
And although soldering is not in any school curriculum, it is such an absorbing activity that it's an ideal way to present topics which are. "The workshop introduces current flowing round a circuit and basic electrical components," says science communicator James Hutchby.
"Then there's electricity as a form of energy; conductors and insulators; and the construction of battery-operated circuits.
"Small fingers are an advantage for this kind of work and the children's ability to concentrate is remarkable. Each year I dream up new devices.
So this year they can choose to make the bagpipes, a lie-detector that measures skin resistance, a 'wonky wire' which is a game you need steady hands to play, or a Hallowe'en pumpkin that lights up at night."
On his desk, a strange-looking device with conducting-wire legs, long antennae and flashing red eyes, suddenly comes to life.
"That's Insectoid," says Hutchby, "a more advanced project for the older kids. It responds to light and sound and contains a computer chip so it can be trained."
"Chirrup, chirrup," says the electronic insect.
"Shut up," says Hutchby.
The little beast looks abashed and falls silent.
But after a minute it can contain itself no longer, gives its antennae an exploratory waggle and bursts once more into a loud trilling song.
The Madlab electronic workshop will tour schools February 14 - March 10, and is a regular feature at the Festival. The school show is aimed at Primary 4 to 7. To book, tel: 0131 473 2070