Christopher commented primarily on the "Unintentional informal learning." I was interested in a different part, one that I work in much more. By the graphic, it would seem that assignments where the teacher gives either the goal or the process, but the other is determined by the student, would be "Intentional informal learning" just as would an assignment where the student determines both. To me, those three feel quite different. I'll have to go read what Vavoula means by "informal". I'll also have to consider what "explicitly defined" means. What if I have a general process, but the students are free to work creatively within that process? What if I have on overall subject goal, but students define many of the elements within that goal? Seems to me that there are many shades of formal and informal learning.