However, I would like to take issue with the idea that experiment ("just try it") is a good way to learn what a particular statement or method does. It's all to easy to draw the wrong conclusion.
It's not like we're dealing with a "black box" here. You can just read the Sun Java Tutorial, the Sun Java API, or the Java Language Specification on the Web. I think that's a much better approach to encourage in new programmers.
Betty Rubble? Well, I would go with Betty... but I'd be thinking of Wilma.