The first 3D project I did with my HS kids this year gave me many headaches. Many students were frustrated because it was HARD! It really wasn't that hard. Challenging yes, but still do-able. I wouldn't ask my students to try something I knew they couldn't do.
Their assignment was to create a wire insect using volume. I had only a handful of GREAT insects in the end. Many students just flat out gave up and handed in poor projects knowing they didn't do so hot. I'm still wondering if it is something I want to pursue again in the future or not. Perhaps a different approach to make it "easier" for them can be found. We shall see.
This one is huge and my student used extremely tough wire! I kept the chair in the picture to show the actual scale. I was very impressed!