Ruby-Rails : lessons on rails ActiveRecord vs plain old rails objects

Got distracted from doing the Agile-Web-Development-With-Rails examples, am now starting from scratch on an experiment with jquery and rails. I'm looking to see what I can achieve from a robust client app with rails based data & services via ajax.

1) Unit Tests throwing " ActiveRecord::StatementInvalid: Could not find table 'panels' "

Kept seeing this error for several basic assert statements in the model unit tests.
> assert p.is_a(Panel)
> assert p.display_text == 'backlog'

Noob mistake here... using 'rails g model' for objects that will not be stored in the database. Caused the objects to inherit from ActiveRecord class, and when ActiveRecord triggers automagic that expects a table to exist for the Panel class, and complains when it doesn't.

Instead, I really wanted to be dealing with plain old ruby objects, and viola! once I deleted the ActiveRecord reference in the model object.

> couldn't use is_a, instead had to use ruby method is_a?
> have to define the accessor methods for private instance variables.