If you are interested in the 3D design process with your own students, I have created a few videos to show how my students created their keychains/nametags using www.tinkercad.com. My apologies for the last video as the quality is not as good (my computer didn't like having that many recordings open, but I will redo it sometime before next year rolls around.
We were finally able to finish printing all 3rd and 4th grade name tags! It's pretty exciting to see them all hanging on the wall and the students are very proud of their designs as well.
We learned some valuable lessons along the way about making things that are too delicate and about how long it takes to print 130-some name tags :)