This article looks critically at the complexity of the debate among climate scientists; the controversies in the science of global temperature measurement; and at the role played by "consensus." It highlights the conflicting perspectives figuring in the mass media concerned with climate change, arguing that science teachers should be familiar with them, particularly given the sharply contested views likely to be brought into classroom discussion and the importance of developing intellectual scepticism and robust scientific literacy in students. We distinguish between rational scepticism and the pejorative meaning of the expression associated with attitudinal opposition to global warming--similar to the way in which Bauer (2006) contrasts "micro-scepticism" and "macro-scepticism" in reasoning generally. And we look closely and critically at the approaches which teachers might adopt in practice to teach about global warming at this difficult time.