Bob, one commenter, suggested Ruby Quiz as another great source to help learn Ruby.

Ruby Quiz posts different problems, which I believe are a little harder than Code Golf, but it has one great advantage. After trying the problem yourself you can look at other’s solutions to the problem. this may help you notice different methods that you have not yet thought of, and may help you learn more about syntax, and functions that are not as readily documented. This can also be a great source for code snippets, but remember to give credit where credit is due.

I have used Ruby Quiz in my pursuit of knowledge, but forgot to place it in my first article. Thanks, Bob, for your suggestion.