Docs:
apidock
railsapi
rails guides
envylabs rails cheatsheet

Teaching tools:
hackety-hack.com/
codeschool.com/courses/rails-for-zombies
codeschool.com/courses/try-ruby
rubylearning.org/
railscasts.com/
teachmetocode.com/
rubyrogues.com/
ruby.railstutorial.org/
guides.rubyonrails.org/
rubyflow.com/
refactormycode.com/
pry.github.com/

Screen / pod casts:
peepcode.com/screencasts/ruby-on-rails
rubyshow.com/
www.destroyallsoftware.com

irc:
#rubyonrails (irc.freenode.net)
#ruby (irc.freenode.net)

Books
Why's (Poignant) Guide to Ruby
The Pickaxe
Beginning Rails 3
Beginning Ruby
Humble little ruby book
Exceptional Ruby