David C
davidActivities, the Achievement Feed concept and its relation to Kolb's reflections on experiential learning models
Kolb (1984) Experiential learning: experience as the source of learning and development:
Kolb introduces the concept of "Experiential Learning" with the Lewinian and Dewey Experiential Learning Models (as well as Piaget's which is somewhat more detailed to include reflections how learning takes place at different developmental stages)
In essence these models describe a "learning feedback loop" of four phases.

The Lewinian model describes them as:
Concrete Experience -> Observations and Reflections -> Formation of abstract concepts and generalisations -> Testing implications of concepts in new situations
and Dewey, perhaps more concisely:
Impulse -> Observation -> Knowledge -> Judgement
In the Lewinian model, "Concrete Experience" refers to the learner undergoing some sort of interaction, or in Dewey's an impulsive action by the learner. I see this is a sort of "play", experimentation or exploration, where within an environment actions are made and the outcomes are discovered.
In the context of an online activity/course system, this stage is the interactivity component of an activity, an environment (some virtual activity world) in which a learner has a concrete experience.
The "Observations and Reflections" phase maps to the learner reflecting upon the results learned from their play/exploration/experimentation within the virtual activity world. This is the learner reflecting on the results and the effects of performing actions within the activity space, and beginning to define some of the relationships between a performable action and its effects, and beginning to form generalisations. The previously mentioned scrapbooking mechanic tries to capture these reflections, or "aha" moments by providing a small area to micro-blog reflections when an achievement (praise) is given, when the task is completed.
Now that I am reflecting on this, I am thinking it may be worth introducing a mechanic which allows these "aha" moments to be captured during the interaction with the activity environment (not just upon completion, depending on how long a task takes to complete and how much it covers). Already we've experimented with a "Task Blog" concept, which in a way caters for this - it is however a fairly heavy-weight thing. Ideally, I'd want a system that captures "aha" moments itself, however in its ideal form this may require mind-reading. A compromise is to try to capture micro-reflections, minimising the barrier to the student, encouraging them to just "brain dump" whenever they have thought up something of note.
The formation of abstract concepts/generalisations from these reflections is what I'd like to capture in a portfolio (along with the reflections that led to them) as well as a "student generated textbook". I find it's really exciting as a learner when I've experimented, reflected upon the results of this experimentation and then come up with concepts that align to those published, in the course content or in the textbook. I find this to be a much richer way of building an understanding of the content rather than the inverted: Look at the concept first-> Practice the concept -> Try to understand where it came from, type of process: If one asks for a fish, give them a fishing rod.
Perhaps the aforementioned achievements system could also have built-in mechanics for building these abstract concepts and ways of discussing new situations in which these concepts become useful. I'll ponder (along with the integration of the community we have available in our online teaching system) how this could be achieved.
So I guess this is my model of experiential learning, in terms of the thought process I'd like to foster:
"This is fun to fiddle with." -> "Aha! I'm figuring something out" -> "Wow, this is actually a type of thing" -> "What else does this let me do?" -> (and back to the beginning again, with a new impulse to explore further)