Who needs to be oriented?

This week all four of my children start at new schools.  One begins junior high, another high school.  One is a freshman in college, and the other a new transfer student.

Of those four, only the freshman in college has an extensive orientation--four days of small group meetings, info sessions, activities, meals, friend building, instruction in rules, assessments, meals, and a convocation with speeches and a gantlet of faculty in academic robes.  Parents are part of two days of these events, where they are wined, dined, and oriented themselves to how to be the parent of a freshman.

On the other hand, the transfer student gets half a day, the junior high schooler gets one day where her grade is the only one in the school, and the high schooler gets a two hour assembly punctuated by pizza.

Why is this?  Is there some reason to believe that the transition to college is a more significant step than the rest?  Is there something about being 18 that needs more transitional guidance than being 20 or 15 or 13?

As a dad, knowing my own kids, their needs, concerns, strengths, and fears, and as an administrator, knowing the goals of orientation, I would certainly assign orientation differently, and according to the actual kids, not their generic transition from one stage to another in life.  I think my high schooler needs a slower, longer transition.  The transfer student could use a period of guided reflection on how to move ahead at a new, different college.  The freshman told me herself that the longer the orientation the more anxious she feels, so I would skip her orientation until after a week of classes.  And my youngest, most gregarious daughter would get a couple of parent-teacher conferences one-on-one before launching into her new social life.

Asked more simply I wonder this: if we oriented students according to themselves, not to their grade or school, how would orientation be different?  Would it be more effective?