There are many benefits to 3D printing. In the classroom it gives student the opportunity to transform 3D digital concepts into physical 3D objects. There is a special experience when students can touch and feel the creation they think up.
One of my favorite stories on how 3D printing has impacted people originates from Marblehead, Massachusetts. Its about a young boy whose father found some people who were making low-cost 3D printed prosthetics. Since the boys family couldn't afford a conventional, $20,000+ prosthetic, this affordable solution has given the boy the opportunity to live his life like he never had before. Check out this news video that covers the story. It is very inspiring and a great vignette to show your students.