I've used Alice (Java) to teach programming to my daughter. But I don't 
think it's really a good way to introduce the basics of smalltalk or 
even Java...

I also have used scratch.

If the intent is to use programming learning material written in squeak, 
I think scratch is a really good tool. Otherwise, one could take a look 
at Etoys which is much closer to teaching to program in squeak/smalltalk.

CdAB