I've tried both Coda and Textmate but Sublime Text 2 just seemed to hit the spot for me especially since the thing is 100% free.
For this course we need an HTML editing tool. There are many to choose from. We do not need many advanced features for this basic course so pick a simple text editor with syntax highlighting.
There are several HTML editors that you can use in your web browser:
The following text editors have syntax highlighting and are Free/Open Source tools:
I chose Bluefish since I'm working on Max OSX
Here's a link to the task: