I know the reflex is going to be to say yes, but I would say it's an 
intermediate topic.  The reason is that I think unit testing shines the 
brightest in later revisions to your applications (making sure changes 
didn't break code).

A possible way is to make a theme like they did in Dolphin.  In Dolphin the 
tutorial is about making a minimal bank account program.  Someone wrote 
tutorials about how to extend these later.  I think that could work.  You 
make your simple Morhpic app, then in the next installment you explain the 
features your application doesn't have but needs and so you explain that you 
want to first make unit tests to ensure you don't break anything.


>From: Matthew Fulmer <tapplek at gmail.com>
>Reply-To: The general-purpose Squeak developers 
>list<squeak-dev at lists.squeakfoundation.org>
>To: squeak-dev at lists.squeakfoundation.org
>Subject: Should Test-Driven Development be in the beginners tutorial?
>Date: Thu, 21 Sep 2006 20:25:17 -0700
>
>On Thu, Sep 21, 2006 at 06:47:52PM -0700, Matthew Fulmer wrote:
> > I created a document stating the plan, goals, and purpose of the
> > Squeak Documentation Team:
> > http://minnow.cc.gatech.edu/squeak/5870
>
>I really want to introduce beginners to (and learn myself) how
>to write good unit tests, then develop a  class that conforms to
>those unit tests inside the debugger. I have heard that that
>capability is one of the best things about Smalltalk, and I know
>that unit tests are a *very* good thing to use.
>
>Should I expose a Squeak beginner to this topic early on?
>or should that be the topic of a separate tutorial?
>
>I do not know if my tutorial will target novice programmers or
>not.
>
>--
>Matthew Fulmer
>