The holidays are all about traditions, and this year at Sketchfab we’re starting a new one: 3December. It’s an opportunity for you to challenge yourself with a new 3D scan topic each day for 3 weeks.
Topics will be announced each day from December 3rd to December 23rd, and you will have until January 1 to complete your models - so even though we’re a few days behind you can catch up over the holidays 
https://forum.sketchfab.com/t/welcome-to-sketchfab-3december-2018-read-this-first