($ = not free)
Curriculum(not only ruby and rails, more complete formation):
Very good fonts, links and information, very good structure!
$ Similar to Odin Project ($= Few days trial period).
Tutorials & exercises
Very good explanations, ruby basics and rails 4.0 ($= Few days trial)
Some free courses ($= sometimes they offer trial periods and discounts)
More typing style:
Learn Ruby from exercises and step by step.
Ruby User's Guide:
A good guide for Ruby.
Ruby documentation in your console:
*If you use rvm it will generate the ruby version that you are using,typing in the console:
'rvm docs generate'
The same but in your browser.
Ruby on Rails guides:
Ruby User group, meetings every first Thursday of the month.
Beginning Ruby From Novice to Professional, Edition By Peter Cooper
Practical Object-Oriented Design in Ruby: An Agile Primer (Addison-Wesley Professional Ruby Series)
Programming Ruby 1.9 & 2.0 (4th edition): The Pragmatic Programmers' Guide by Dave Thomas, with Chad Fowler and Andy Hunt
Interesting video about ruby vs other languages(Nov 2012):
Infographic against the learning Pyramid(Pyramid of Dale) and about effective learning: