In 2016, I helped Rippl3D, a company utilizing 3D printing for design challenges, run a 3D printed rocket competition at IMTS. A participant builds a rocket with a nose cone, body, and tail fin to hit a target. The contest allows iterations to adjust nose cone weight, different tail designs, and the take-off angle to improve their score. An advanced option will enable students to design and print their tail fin design with an onsite 3D printer.
Recently Illinois Institute of Technology (IIT) had a STEM day for local high school programs and asked for help setting this challenge up. Parts were printed on a Stratasys Fortus 250 in ABS, and Southside Hackerspace designed the air launchpad.
The event went well and had about 250 students participate in the challenge.