> Although every school in my county has a few 3d printers, so some schools could print directly.
Shared 3D printers almost always produce poor quality, inaccurate prints. Never mind maintenance, using them requires skill. Skill which teachers usually lack, and schoolchildren obviously lack.
They're still useful devices, but I wouldn't expect such prints to be strong enough and accurate enough to do the job.
Although every school in my county has a few 3d printers, so some schools could print directly.