One of the primary teachers gives a little gasp of dismay when presenter Suzanne Ensom gets to the last part of her description of an unusual but effective form of debate.
"People are up in a hot-air balloon when something goes wrong. They'll all fall to earth unless they get the weight down. Each person gives a talk saying why they should be saved. The ones judged best stay in the balloon. The others are thrown over the side."
Despite the sharp intake of breath, the balloon scenario has several advantages over conventional debate, Ms Ensom tells the teachers at the continuing professional development session organised by Glasgow City Council and delivered by the English-Speaking Union. It lends itself well to tackling many-faceted situations, unlike the usual format of small teams for and against a motion.
"This is a key aspect," she says. "You'd like to be able to bring debates into any topic in the classroom. Many will have more than two points of view."
Effective at its most basic, the balloon scenario can also be made more sophisticated, she says. "With planning, you can continue over several lessons by making speakers eliminated in the first round into supporters of those that remain - then have them work in groups to research and prepare more speeches."
Motivating children to learn about prominent people from the past or present is by no means the only possibility. They could talk about inventions, such as the internet, television, radio and the telegraph; they could become advocates for regions, dialects, languages or cultures.
Role-play debate is an even more flexible format, says Ms Ensom, which allows children in groups to argue the case for each set of stakeholders in, for example, the consultations over a new by-pass. "You can have groups of residents, planners, local businesses, even wildlife," says Ms Ensom.
Role-play can develop skills and qualities beyond those associated with conventional debate, says Ms Ensom. "Children put themselves into the minds of the people they're playing. They see the pros and cons. They get into negotiations with other groups."
Good debates don't just happen, she tells the teachers. "You approach them as three separate stages - preparation, debate, follow-up. So with role- play, all the rabbits in the woodland could do the brainstorming, research and planning together, then go into mixed groups for discussion and negotiation. Then they could return to their rabbit group to tell how they got on."
Other good follow-up activities include getting pupils to write newspaper articles or produce audio interviews with the people participating, she says. "The most important aspect of these kinds of debate is that they involve a whole class."
But it is also possible to adapt a more conventional debate, so that everyone in a class has a role in the debate and not just in the preparation and follow-up. "Instead of one chair, you can have three, who introduce different parts of the debate. This is nice for children who want to speak in public, but aren't yet ready for a full speech," she says.
"You can have five judges. So already you're up to 14 pupils. The rest get involved in the floor debate, before the summary speeches. You can task pupils to listen to what's said and ask a question. More confident ones can give short speeches from the floor. In competitive debating the floor debate is quite short, but in the classroom you can make it as long as you like."
The other half of the English-Speaking Union's CPD session focused on getting the best from conventional, competitive debates, and was delivered by Aissa Watson, who covered Curriculum for Excellence, how to warm up a class and get children's ideas flowing, and how to prepare and structure a speech.
A number of simple activities, such as "I couldn't disagree more" - in which each speaker round a room makes a short statement opposing the previous one - showed just how hard thinking on your feet can be.
The two-hour session was very well received by the teachers, a number of whom stayed on to chat to the presenters. "Our children do quite a lot of presentations nowadays," says Margaret McCluskey, who teaches P6 at St Brigid's Primary. "So it's great to learn how you can take that further and challenge them more."
Determined to .
The CPD session was part of a process leading to a large-scale debating event in the City Chambers, explains quality improvement manager George Mackie.
"Determined to Debate is one of a number of projects Glasgow has launched, using Determined to Succeed as the springboard. One of the first was Determined to Make Movies, which let the children develop a whole range of skills, such as filming, editing, acting, writing.
"We now have Determined to Animate, to Construct, to Engineer. They're great vehicles for building partnerships between schools and outside agencies, such as colleges, businesses, the Glasgow Film Theatre."
A wide range of activities with a specific, practical focus is what unites these initiatives under the "Determined to" badge, says Mr Mackie. "We are now mapping them to all the Curriculum for Excellence outcomes and experiences - which is a big job. The latest we're working on is called Determined to Rock. It's for the kids who like making music.
"There aren't that many really good educational ideas out there. We think this is one."