The following mini projects to be used as mini lessons/project using Autodesk Inventor in Advanced Drafting courses:
Cup Holder:
https://academy.autodesk.com/portfolios/cup-holder-first-project
Thingverse Popular:
https://www.thingiverse.com/explore/popular/page:1
40 Cool Things:
https://all3dp.com/cool-things-to-3d-print-useful/
17 Cool Things:
https://all3dp.com/fun-things-to-3d-print/
45 Cool Things to 3D Print:
http://tutorial45.com/cool-things-to-3d-print-3d-printer-ideas-3d-printing-ideas/#14
Business Insider 30 Things:
http://www.businessinsider.com/useful-3d-printer-projects-2015-2#this-working-padlock-and-its-key-are-made-entirely-out-of-plastic-1