Write everything down, anything that comes to your mind. Make it the first line of your story. When they've finished, ask volunteers to read out their finished piece of writing.
But, regardless of which you examine, the step-by-step process of our thoughts unfolding is utterly fascinating. Have you ever tried the stream of consciousness technique? Anton Chekhov also followed stream of consciousness writing style.
What is their opinion of what they observe? What do they think?