Some pedagogical thoughts

I've been doing some thinking about teaching in the fall, and how I'd
plan out courses--especially have been thinking about trying to teach
the Environmental Policy class I taught a year ago once again. I really
wasn't satisfied with the way the course turned out, and I'm hoping I
can do a better job the second time around.

I've made some half-hearted attempts to put applications for writing
fellowships together for next year, but really haven't had the time, and
to be honest, I'm really looking forward to teaching again--I miss it.
Of course, who knows if it will even be an option? I may yet be
press-ganged into TA-ing "Intro to Comparative Politics: for the seventh
(?) time. Or grading. Terrible.

Nevertheless, I've been giving some thoughts to pedagogical technique.

Conventional wisdom in teacher circles suggests that students retain a
very large percentage of material (something like 90%) of material they
teach to other students several weeks after they've taught it. On the
other hand, students retain a correspondingly low percentage of material
which they are "taught" in a lecture format (something like 10%). This
seems to imply that we should be doing a lot of student-centered
learning (students presenting in front of the class and whatnot).

There may be something to this, but I have large concerns.

First, where do these figures come from? Statistics like this are
rampant in the secondary education community, but I've never read a
study or seen a citation. Maybe the figures are true, but maybe they're
not.

Second, these figures don't take into account variations in learning
styles, and variations brought about by varying student techniques. For
example, students who actively take notes, versus students who stare
into space, students who attempt to become actively engaged through
discussion and questioning versus students who don't and variations in
lecture styles (certainly, some lectures are more memorable than others,
right?)

Finally, these figures fail to take into account (a) the fact that while
one student is teaching in front of the class, others are learning, and
(b) students' teaching techniques are typically not as good as, say, 30
year-old former secondary school Social Studies teachers with
ostentatious moustaches. Often, students give poor quality
presentations/lectures, and even when they're trying hard, they often
fail to impart the most important parts of a given topic.

Further, in large classes, student presentations and other types of
student-centered learning take up large amounts of time. In the
environmental policy class I taught, for example, there were about 80
students--trying to do presentations can take weeks (and usually does)!
This is an awful lot of crappy teaching for one class.

So, where do you draw the line?

I've been thinking of moving to individual student presentations (or
small) group presentations which students present to a smaller group of
students, basically so that the students have the benefit of presenting
and teaching, but so that the presentations don't take up so much time.
If I break an 80 student class into groups of about nine (three groups
of three) and then have each group of three present to two other groups
of three (basically in a circle), we could presumably have everyone
present 10-minute presentations in a class period, and 20-minute
presentations in a class and a half.

Any of you pedagogical wizards out there have any thoughts on this nonsense?