Watch water boil at room temperature.
The temperature at which water boils depends on pressure. You can demonstrate this by dramatically lowering the pressure on a water-filled plastic syringe at room temperature.
Full instructions for this activity are available at https://www.exploratorium.edu/snacks/boyle-ing-water
Science Snacks are hands-on activities, projects, and experiments that are designed for the classroom and the curious. They're cheap, simple, safe, scientifically accurate, and teacher tested. Want to see more? Check out http://exploratorium.edu/snacks.