Heat fluxes are a topic that at first seems pretty theoretical, but with which we have tons of experiences in our everyday lives! A quick brainstorm for where we experience different types of heat fluxes gives so many examples:
Asking students to come up with their own examples to discuss makes discussions a lot more fun and a lot more relevant to their own lives. Suddenly, a theoretical discussion becomes about explaining their own experiences, and possibly informing future actions (like for example with how to best cool a beer bottle on a hike). This works for any topic and opens up a whole new world to students when they suddenly see the topic applied in situations that they, or their peers, have personal experience with!