A project I am interested in is not in the calendar

Make sure that when you find a project you like you click on the Follow button in the top right hand corner of the project. Then it will appear in your calendar, any updates will appear in the My Project  Updates section, and will also appear in the Projects I am Following section.

To follow / subscribe to a project, watch this helpful video: https://www.youtube.com/watch?v=ojps_xcUgeQ