Why do you want to make it residential? If you are not in London, would you consider taking them there? I have taken my Yr12 students (who take the same course as yours) on day trips to the following places over the years: the London Planetarium (ties in with the Cosmological Argument / Religion and Science etc.) the Freud Museum (Freud's views on religion / conscience) the Tyburn Convent (Religious Experience) various temporary exhibitions (e.g. the 'Treasures of Heaven' at the British Museum last year or the 'Sacred' exhibition at the British Library some years ago); this year I am taking them to the National Gallery and am making up a quiz on the religious paintings there. Even if it does not tie in very closely with the syllabus it is still an enrichment activity as many of my students have never been to those places.