Stream of consciousness

For my Modern British Literature class, I finished "Portrait of a Young Man" this week by James Joyce.  It is not something I would normally pick up to read, but I found that once I got past the new structure, I really enjoyed it.

I wonder sometimes why "stream of consciousness" never became more popular?  It seems like it would be so easy to write.  My sixth graders all seem to write that way (which is rather frustrating to read, since unlike Joyce, they never seem to come back around - they just circle and circle).

It is hard to read, but is that only because I am not used to reading things like this, or would it always be hard to wrap your head around something that is written as though you are wrapped up in the protagonist's brain?