This is a writing exercise for the student, and answers will vary.
Work Step by Step
Sample: Hello Grandma. Objects are always exchanging radiation with their surroundings. You know how you like to cover your prize roses with a thin blanket at night when the temperatures may drop close to freezing? The plants then radiate to the blanket, which is warmer than the night sky, and lose less energy. Clouds do the same thing for the Earth as the blanket does for the roses. That's why the air is generally cooler on clear nights, and warmer on cloudy nights. The silver lining on your thermos bottle works the same way, reflecting radiation from your hot tea back to the tea. All things continually emit and absorb radiant energy.