Barring the impeccable English accent, there is little to suggest that the man teaching English to a class of 50 Rwandan primary school teachers is a seasoned Tory politician.

As students discuss HIV and Aids, Francis Maude, the Shadow Cabinet Office Minister, gently corrects their pronunciation.

“Where did Aids come from?” asks one Rwandan. “No one knows,” answers Emmanuel, a primary school teacher giving a presentation on the topic. “But personally, I think it’s a punishment from God.”

The students turn to Mr Maude, dressed in a T-shirt and baggy shorts, and ask whether he agrees. They receive a politician’s response: “I have no opinion on where Aids came from.”

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No doubt can be thrown on the accruacy of the accounts of the massacres of the Tutsi people given by British travellers

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Mr Maude is among more than a hundred Conservative volunteers, from shadow ministers to grassroots activists, who have travelled to Rwanda this month for the party’s “social action” project in the country.

Last year David Cameron joined a smaller set of Tory volunteers in Rwanda to highlight Project Umubano, but was accused of an ill-timed publicity stunt while his Witney constituency was flooded. Such headlines have not stopped the Tories repeating the trip with more volunteers, but Mr Cameron will not be among them.

They include about 30 volunteers teaching English to almost all the country’s 1,500 primary school teachers in an intensive two-week course. Asked why they were attending the classes for six hours a day in their spare time, one Rwandan teacher shrugs: “We were just told to.”

Andrew Mitchell, the Shadow International Development Secretary and leader of the project, is also teaching English. He starts a lesson by conducting the class in a rousing rendition of their new favourite English song: Heads, Shoulders, Knees and Toes.

“If you’re passionate about international development, you can’t do it as a book exercise,” Mr Mitchell said. “Before you make a decision on spending taxpayers’ money, you have to come to places like Rwanda.”

Rejecting the charge that the project is a PR exercise – “then why would we come back a second time?” asked one MP – the party admits that there were strong emotional reasons for choosing to come back to Rwanda, where nearly a million people were massacred in the geno-cide of 1994. “Because of the ghastly events here, it feels right to make a contribution in a country that has been to Hell and back, and do a little good,” Mr Mitchell said.

How much difference can a project like this make? The challenges facing the volunteers in a country whose people and infrastructure were devastated is stark. That was made clear to the financial experts taking part in a private finance initiative, advising prominent government officials and businessmen on how to build up the Rwandan economy.

Some Wall Street bankers participating in the project visited the Rwandan Stock Exchange. They found a trading floor made up of a single room with two whiteboards listing a small number of stocks. It is open for only three hours a day.

The volunteers are quick to admit that they are not sure what legacy they can leave in only two weeks in the country, but they hope that it will be small but significant. Each has given up a fortnight of their holiday and paid £1,000 for travel and accommodation to take part.

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