Pupils from Jewish schools went to Lambeth Palace to receive awards for their Mitzvah Day efforts in partnership with non-Jewish schools.
The Archbishop of Canterbury, Dr Rowan Williams and Reform head Rabbi Tony Bayfield made the presentations to the four schools.
North West London Jewish Day School had partnered with Christ Church School and Ilford Jewish Primary with St Augustine's Catholic Primary to perform a range of good deeds.
Council of Christians and Jews' chief executive David Gifford described them as "young interfaith dialoguers".
North West London Year 6 pupil Adina Davis said: "It's good to learn about religion from a different point of view."
Speaking afterwards, Dr Rowan Williams said: "Because a vision of justice and of service isn't the sole preserve of any one religious group then it is extremely important for the faith groups to work together on that mission."
The Chief Rabbi - who arrived late because of commitments in the House of Lords - was pleased to see the idea of Mitzvah Day "spreading beyond the Jewish community. I would love to see it take hold to wider groups across Britain."
Also present was Mitzvah Day founder Laura Marks, who sees it "as a platform for different faiths to work".