Dr Lewis currently teaches on Introduction to Social Anthropology, Advanced Ethnography of Forest Peoples, Ecology of Human Groups, Hunter-Gatherers: past, present and future, Research Skills in Social Anthropology and Material Culture, Current Issues in the study of Gender and Sexuality and he teaches at the Centre for Social Excellence in Yaoundé, Cameroon. He co-directs the Centre for the Anthropology of Sustainability and the Extreme Citizen Science Research Group, is founder and trustee of the International Society for Hunter Gatherer Research, and is a member of the Human Ecology Research Group and Radical Anthropology Group.

He has previously taught at the London School of Economics (2003-2007). With Dr Luke Freeman he has spent several years developing digital tools for teaching undergraduate anthropology. The course won a commendation from the Higher Education Academy (2005). A resource he designed used text and film to provide students with problems to analyse that simulated the increasing levels of information an anthropologist would have in the field. It can be seen and used at http://clt011.lse.ac.uk:8383/steve/wgo/index.html.