Hi SharePoint Gurus - There are so many site template in 2013. I am looking for suggestion which site template is good fit to use to create a Training Site. I heard long ago about the Educational Service Feature but couldn't find any documents. Other options that I thought of Community Site? 

Need to Invite Members for training, Accept/Reject Invite, Track which employee took what sessions/lessons; comments and recaps from previous sessions, and a description of each of sessions

R

You can get it from codeplex, though it is for SP2010, you can convert that to 2013 templates.

https://sp2010teamplates.codeplex.com/ > Employee Training Scheduling and Materials