Keeping a class of boisterous teenagers quiet for an hour is never an easy task. Less still if they are being asked to listen to a guest speaker who wants to discuss national health policy and the legislative process.

Fortunately for Sarah Sackman, the sixth-formers in question, at Finchley’s Christ College, were politics students, and quite happy to be meeting a general election candidate.

Ms Sackman, standing for Labour in the Tory-held constituency of Finchley and Golders Green, faces a tougher challenge in her bid to unseat Mike Freer, who has a majority of just under 6,000. But the 30-year-old lawyer, in her first general election campaign, is up for the fight.

She has a CV that belies her age, having already worked as a foreign law clerk at Israel’s Supreme Court in Jerusalem and for campaign groups and social justice causes. Before that there was a scholarship to Harvard.

But will her background impress the voters? “I think people would say I have the maturity to do this. I have the sort of experience that’s relevant to the job,” she told me over coffee in a cafe next to her East Finchley campaign HQ.

“Work in the community was always part of what I did and this is an extension of that. What I do for a living is represent people to try to progress the law and their interests. In many ways, that’s the role of the MP.

“I am passionate about what politics should do to advance social justice. That’s why I chose to do law and why I’ve decided to stand in the election.

“We need more women in politics. There are more men in Parliament today than there have ever been women MPs in the entirety of our democracy. It’s incredible.”

Raised in East Finchley, Ms Sackman’s maternal grandparents were from Spain and Gibraltar, where her grandfather served as a minister in the government. A member of the Jewish Labour Movement, she has often spoken to audiences about the influence of her Jewish upbringing on her politics.

She is a persuasive character — there is lots of eye contact, some self-deprecation, and an apparent qualification from the Tony Blair school of hand gesturing.

Labour leader Ed Miliband took a tough line over Israel during last summer’s Gaza conflict. She accepts that her chances in the country’s most Jewish-populated constituency could suffer as a result, but says: “I have very strong ties to Israel, I have family there, my husband’s family come from Israel. It’s a deeply personal commitment.

“People are interested in what happens in Israel. But what dominates their thoughts are the daily concerns — the economy and the cost of living.”

Ms Sackman makes a convincing argument against the concept of a “Jewish vote”, pointing out that identifying with Israel does not mean British Jewry en masse follows a single political preference.

“The community’s opinions on the actions of the Israeli government are divided. That’s a good thing. There’s no uniform, one-size-fits-all approach in the Jewish community, and that’s as it should be.”

She knows she is up against it, but takes heart from the fact the election is one of the most unpredictable in years.

“We are bucking the trend in London and doing very well. Yes, it will be a hard fight. Ed Miliband came to visit here, Shadow Home Secretary Yvette Cooper came; the party has a real commitment to winning this seat.”