A while back I ran many of the individual frames through Bobby.  A lot of
images without alt tags - mostly eye candy but that doesn't help the user
who can see that it's an image they can ignore.  Other than that it did
pretty well.  There are two fundamental problems, however.

1) There are a lot of different frames and I didn't test them all.  In
particular, I didn't examine the communications tools very closely.

2) Whether the content is accessible is something that Blackboard doesn't
really control and probably where accessibility is going to break down the
most.

I've heard that Blackboard is making accessibility a goal; I think I may
have posted to this list their announcement a while back. But when that's
really going to have much meaning is not clear.  I don't think it's crept
into 5.0 to any great degree.  But 5.0 needs help so maybe it will be there
with 5.1 or .2 or ...

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Paul Chapin
Curricular Computing Specialist
Amherst College
413 542-2144