This article presents an approach to integrating public e-lectures on contemporary physics into a traditional high-school syllabus. This approach was used in a long-distance professional development course for in-service physics teachers. Each lecture was related to a specific obligatory syllabus chapter, and was accompanied by learner-centred activities. We provide a detailed description of an activity that explicates the scientific arguments that were presented in the lectures. Teachers appreciated the approach and reported that the lectures and activities updated and broadened their knowledge of physics and contributed to their understanding of the nature of science (NOS). (Contains 3 figures.)