For example, this excerpt from my story Bookwarm, clocks in at College Graduate:
Although many complain about the horrors of the subway, Castiel finds in it a lot of positive qualities. In the summer, where even in the early hours of the morning the heat looms threateningly, the train provides sweet relief from the hellish and sometimes stifling weather; the cool air that rushes out when the train doors open are a welcome reprieve. In the winter, when the snow and consequent icy sludge that follows consumes the city, the flood of warmth that blows as the door welcomes him in, heats up Castiel’s cheeks and leave them tingly and rosy.
And this excerpt from my story Beached, clocks in at 11th - 12th grade:
You had met him weeks before on a chilled, Tuesday morning. You were jogging along the boardwalk, the storm-battered wood creaking below your feet, when he just appeared. Though, maybe, appeared isn't the right word. It was foggy, the beachy air filled with heavy, salt-laden mist, and as it cleared, there he stood.
While this excerpt from my story Double R, clocks in at 7th-8th grade:
I woke up the next morning, sitting in Ryan’s lap with my head on his shoulder. It was about five in the morning. I swallowed some Advil - for my headache - and changed into to clean clothes. By the time I was dressed the bus had pulled up to the hotel. Of course everyone was still asleep. I caught the driver before he went to wake up the guys and I told him I would. I went to the back of the bus and stood where Ryan was sleeping. I kneeled down next to him and leaned over to his ear.
I think this function is pretty interesting and could be very useful to writers. It might be important to know how your story's reading level matches up with your intended audience, and to see if that might be negatively affecting your story's success. For example, if you're writing a story for young children, but it's at 12th grade reading level, that could explain why you can't gain any traction with that age group. Or, if you're writing a novel for new adults, but it's written/reading at a 8th grade level, that could also be why you're not gaining an audience.
Anywho, I just thought that was kind of interesting.
If you're interested in checking this out for your story (or excerpts from your story), you can find it here. You can also share your results in the What's Your Story's Reading Level? thread.