Since I just compiled this list for the RubyLearning forums, I might as well post it here. Below you’ll find articles I often recommend to our students, plus some personal favorites:

• The Unofficial Ruby Usage Guide


• The Ruby Object Model – Structure and Semantics


• Seeing Metaclasses Clearly


• The Ruby Singleton Class


• A Ruby Metaprogramming Introduction


• The Fully Upturned Bin


• Writing Ruby extensions


• Untangling Evented Code with Ruby Fibers


• Tailin’ Ruby


• Demistifying IRB’s Commands


• Everything You Need to Know About Unicorn