Gordon Brown has denied his "citizens' juries" are simply a glorified photo opportunity, as the first one meets in Bristol to discuss children's issues.
Mr Brown says he wants to engage more people in politics.
The prime minister said he had already changed his mind on casinos and cannabis after listening to the public.
He says the juries signal a "new type of politics" and will shape policies.
He added he did not want to see guns become "accepted", as they were in the US - as thousands attended the funeral of 11-year-old gun victim Rhys Jones.
He told the citizens' jury in Bristol: "We want to get guns out of every community where there are guns and we've got to set that boundary very clearly - about guns, about bullying, about violence, about knives and everything else."
The first citizens' jury - a group of 12 to 20 people, picked independently to represent a community - discussed issues affecting children like school discipline and internet pornography. Another meets next week to discuss crime.
They hear from a range of experts before reaching a conclusion, which will then be presented to ministers.
The Bristol jury was comprised of two tables of parents, two tables of pupils, one of teachers and a random selection of residents.
Asked whether they were just a photo opportunity, Mr Brown told the BBC: "No, because we're changing our mind when we hear what people have to say.
"We changed our mind on casinos, we've changed our mind on cannabis; it was a result of me going around the country, listening to people, hearing what people had to say."
He said he expected proposals on school discipline and the curriculum, video internet violence, pornography, poor diets and obesity to come forward.
"These are all matters that parents, every parent in the country has strong views about and we've got to listen to what they say," he said.
Children's secretary Ed Balls told BBC Radio 4's Today programme: "We need to involve parents more - particularly fathers more."
But shadow work and pensions secretary Chris Grayling accused the government of "always launching public consultations" adding "neither Gordon Brown nor any other minister ever pays any attention to what the public thinks".
He said: "There's a real danger that this whole exercise will be a complete farce."
Meanwhile the Liberal Democrat leader Sir Menzies Campbell has said British politics is in crisis, with voter numbers in decline, and a "real sense of grievance" about decisions being taken on which they feel they have no influence.
He is proposing that people should be drawn by random lot to join a convention working on Britain's first written constitution, to prevent it being taken over by constitutional reform "obsessives".
He told the BBC: "What we've got to ensure is it's not politicians talking to academics talking to politicians.
"If we're going to engage the public the public have got to feel that they've had a real stake in the creation of a constitution fit for this century."
He said consultations took place "almost on a weekly basis" but were often "simply disregarded once the decisions were made".