The 'T-MEDIA' project analysed and documented how teachers exploit the use of projection technologies - data projectors and interactive whiteboards (IWBs) - to support learning in secondary-school subject lessons. The research involved collaboration between university researchers and eight UK secondary teachers in four subject areas. This article reports on a follow-up study carried out one year after the collaborative analyses in order to assess: (1) the subsequent impact upon teachers' own pedagogical thinking and practices; and (2) the extent to which the ideas and practices they developed had been shared with, taken up and adapted by their colleagues and schools.