There are some great threads of discussion occurring on the IxDA.org site. One of them is an exploration of the difference between interface and interaction design. In understanding the difference and how to communicate it to peers, clients and students, the discussion turned to education and I'm reposting here what seemed like a relevant post on the topic.
There certainly is a lot of crossover between this thread on interaction vs. interface design and one on 'What to teach interaction design students' - and the heart of both topics seems to center around language and understanding.
First, needing to have a clearly articulated definition of the discipline and it's relationship and differentiation from those related. That has been explored well here and it's clear that it is a continuum - there are some whose talents overlap ranging from theoretical to the practical. (I love the author/illustrator analogy, and I'd add David Macaulay to that list!) Think 'theory of interaction' on through interface design, prototyping and the skills to actually develop the site/application/device. It's a rare few that can competently do all of those things, but there are certainly more who can do much and direct the rest effectively.
What Dave [Malouf] has brought up here and in the other thread is a need to effectively critique the work - both by students and I'd say also by practitioners 'out in the world'. In developing the right language and vocabularies to effectively critique, and therefore explain (!) the work. This is vital to the education process and equally so in conveying the value and effectiveness of work being done. In visual design there are more known vocabularies for describing and evaluating design from an aesthetic point of view. However in interface design (such as for the web or a software application) there are additional concerns around usability (affected by the interaction design), how well it solves business objectives and how well/efficiently it can be produced. There is beauty to be found in all - or perhaps at least elegance. The vocabularies to describe a beautiful code solution versus a truly elegant business solution versus a completely intuitive interaction solution are all quite different from the set of words and phrases applied when evaluating color, composition and 'visual tension' found in a great piece of visual design (a painting, a print, a poster or a software interface). In actuality some of the words may be the same, but the theory and criteria with which they are applied is quite different.
So I think that to answer either thread (what's the difference or what to teach) we must first be able to describe and understand both what is entailed in any of these disciplines and how one can describe 'success' in any of them. From there it's easier to say 'I'm an interaction designer' or 'I'm an interface designer' or in someone like Andrei's situation, I'd say that he's more than either in that he may think of himself as an interaction designer primarily, but having the ability to perform and/or direct what comes after (interface/visual design and the actual prototyping and production of the end product) is definitely a broader role. I think we all live in worlds where it flows from Dave's situation of being surrounded by other experts so he can focus solely on interaction design and others like myself and other in this thread who by necessity or desire involve themselves in other surrounding roles. It doesn't diminish the importance of any one of them, but without the language to articulate the differences and importance of the various distinct disciplines then there will always be a danger of important tasks and roles being eliminated from the world.