One of the best free training resources out there is the Microsoft Virtual Academy (MVA). It has a LOT of free training on all topics. A couple of weeks ago, I attended two sessions on “What’s new in R2” for Server 2012, which is a topic I would think most sysadmins would appreciate.
Now the recorded versions of those sessions have been posted online here; What’s New in Windows Server 2012 R2 Jump Start
You get “points” for attending training and can watch your ranking against other individuals.