

Students Ace Textbook Physics While Struggling With Basic Understanding (video) - vinutheraj
http://www.youtube.com/watch?v=WwslBPj8GgI

======
stcredzero
The headline reminds me of Feynman's account of teaching physics in Rio. Every
student could stand and deliver a verbatim retelling of all the definitions in
the textbook. They had just covered polarized light. The classroom had a
beautiful view of the bay, with sunlight glinting off the water.

Feynman asks for and gets a recitation about polarized light, which includes a
bit about reflected light being polarized. He then turns towards the window
and asks the class for an example of polarized light. The whole class is
flummoxed. Everyone could recite, but none of them could _apply_.

EDIT: I remember the day, being a TA for a Comp Sci 101 class, when I realized
that a lot of the most vocal and active members of the class were more
interested in the _mechanics_ of lectures and tests than the material. It was
all a game. I put stuff on the blackboard and in the handouts, and they spit
it out on the test sheet. We have become a society of appearances and
bureaucratic mechanism. Most college students go through the motions and get
their paper, then go home thinking science is just more made up bullshit like
politics. These folks laugh when you talk about evolution as reality, and can
only reason abstractly at the level of a grade schooler. Many of them
graduate, vote, and get promoted to positions of authority.

~~~
dschobel
I'll never forget when I was interviewing a candidate for a junior C#
programming position and the conversation went as follows:

    
    
      me: Can you tell me what a delegate is?
      candidate: <text-book perfect definition, absolutely flawless>
      me: Great! Can you tell me when you would ever want to use one?
      candidate: <silence for about 15 seconds> I don't know.
    
    

It was so bizarre and I still don't fully understand how you can understand
the absolutely perfect theoretical definition with having no, literally not
one, idea what you're learning.

~~~
snprbob86
Personally, I simply cannot _recall_ anything unless I understand it at least
superficially. I may be able to _remember_ if prompted, but my memory is
simply organized around my own definitions and understanding.

Maybe us engineering types are hardwired this way. I suspect, however, that
non-engineering types aren't wired this way due to poor parenting, weak
schools, and fundamentally broken reward and punishment systems.

~~~
CWuestefeld
_I simply cannot _recall_ anything unless I understand it at least
superficially_

Me too. That's why the wheels came off my math skills when I got to
differential equations. Everything up to that point I'd been able to form a
picture of in my head. For example, calculus is just Newtonian mechanics, so
that's got a clear analog in the real world.

But Diff EQ was just too abstract. I was eventually able to pass it with the
help of a couple friends pumping me full of formulas and procedures, but I
never really understood, and so I never could really apply it on my own.

~~~
chrischen
I took a linear algebra class and they explained nothing. Sure they'll prepare
you for their tests, but otherwise their material was way too abstract. Not
until I watched a lecture by Gilbert Strang on iTunes U did I finally
understand what an eigenvalue/vector is and what the hell the matrices
represent.

~~~
mcherm
So, enlighten us: what is an eigenvalue, and what do matrices represent?

~~~
chrischen
So mcherm, I'm pretty sure you don't need any enlightenment on this, but I'll
try to peer teach this to whom it may help.

So let's say we have a vector which is represented by the matrix A of any
dimension (any # of columns, each column a vector). If we multiply this matrix
A with an arbitrary unit vector (considering just the direction in the given
dimensions) B, then we'll have a certain set of possible resulting vectors (A
X B). The eigenvectors are whenever the same unit vector B lines up in
direction with (A X B)--where both vectors are dependent on B, and the
eigenvalues are the corresponding scalars which must multiply the unit
eigenvector to match the resulting A X B vector. The eigenvector does not have
to be a unit vector, but since any multiple of the eigenvector can still be a
valid eigenvector, you probably just want the unit vector or at least the
lowest whole number reduction. If you reduce the eigenvector, the eigenvalue
must be changed too.

In equation form: Ax=Ωx Where A is a matrix you are trying to transform, and x
is the possible eigenvector, and Ω is the eigenvalue.

In graphical form (this was what really did the trick):
[http://ocw.mit.edu/OcwWeb/Mathematics/18-06Spring-2005/Tools...](http://ocw.mit.edu/OcwWeb/Mathematics/18-06Spring-2005/Tools/index.htm)
(Demo #1)

And the matrices are simply a different form of a set of equations while still
preserving their relative properties. The matrix form allows you to easily
manipulate the original set of data with matrix operations. I guess the matrix
can also just represent a set of column vectors (which are just a direction in
a space with a magnitude) too.

Let me know if I got anything wrong.

------
tokenadult
Eric Mazur is a very thoughtful researcher on effective physics education. See
his writings online

[http://mazur-
www.harvard.edu/publications.php?function=searc...](http://mazur-
www.harvard.edu/publications.php?function=searchbyid&author=3)

for articles on physics education from his paradigm-challenging perspective.

------
teeja
This is really excellent ... and it makes you think: we (US) used to have one-
room schoolhouses where _the older kids helped the younger kids_. Another
thought: a lot of the differences between the prof and students would be
removed _by physical discovery_ rather than lecturing.

I never liked lectures. What kept me going was talking to people and DOING
stuff. And those things I retained for DECADES ... the rest was gone in a year
or two.

------
mquander
This title was suggested verbatim by JabavuAdams in a recent thread:
<http://news.ycombinator.com/item?id=1022269>

I think it's slightly unethical to take it word-for-word without giving a hat
tip.

That said, this is a rather remarkable video if, like me, you don't know much
about the theory of education (I showed it to a smart friend who teaches
undergraduate literature and he said that it was all old hat to him.)

What really stood out to me was the hard data behind Mazur's conclusions --
it's "common sense" that students do better when engaging in the process of
learning, but I had never before seen it so convincingly demonstrated.

~~~
vinutheraj
Sorry! I waited a day for you or JabavuAdams to post the link, but since you
both didn't do it, I posted it myself, because I felt this was good enough to
be posted here !

------
RK
When I was in physics grad school we used the Force Concept Inventory for
assessing the intro level physics classes. It was always very interesting and
showed that they were able to greatly increase understanding over the course
of a few years by focusing on a few areas.

I feel that (introductory) physics education has benefited greatly from
education research, partly because data can be easily collected and at
universities you can adapt and iterate on a semester (or annual) time scale.

It would be nice if this model could be adapted to other areas, such as
graduate physics, but the normal response is that grad students are supposed
to be responsible for their own learning...

------
DaniFong
For anyone who this video resonates with, I suggest watching the highly
entertaining Bollywood hit 3 Idiots, about three mechanical engineering
students a a prestigious indian engineering college, struggling against their
autocratic principal :-)

------
cabalamat
If you can pass the exam without understanding the subject, the exam is badly
designed.

~~~
mquander
That's true, but it puts teachers at a post-primary-school level in a real
bind. It's hard or impossible to take a subject like physics or calculus (or
even algebra, or English literature) and teach it from first principles in a
semester or two, especially when most of the students are not very self-
motivated or interested _a priori_ in the work.

So what do you do when you have a class full of students who have already been
basically failed by the system and who understand none of the foundations of
your subject? If you fail them all, you're the one that is likely to get the
ax, even if it's true that none of them understand your material. Most
teachers resign themselves to doing their best and administering fairly
traditional tests and classwork, so that hard-working students can pass even
with no understanding.

~~~
cabalamat
You're right, which is why teachers/schools/education authorities shouldn't be
setting the exams. The purpose of the exams is (or should be) as much to check
that they're doing their job as it is to examine the children.

~~~
yummyfajitas
True, but in practice this isn't what happens. What usually happens is that
low performing teachers (or school systems) lobby to have the standardized
exam watered down.

This is a fundamental problem of agency costs. The only people who gain from
having a good testing system are the high performing students, and we
obviously can't put them in charge.

~~~
cabalamat
> What usually happens is that low performing teachers (or school systems)
> lobby to have the standardized exam watered down.

In Britain, where the exams have been dumbed down significantly -- see
[http://cabalamat.wordpress.com/2007/08/31/gcses-are-
dumbed-d...](http://cabalamat.wordpress.com/2007/08/31/gcses-are-dumbed-down-
and-getting-worse/) or [http://cabalamat.wordpress.com/2009/03/30/do-you-see-
with-yo...](http://cabalamat.wordpress.com/2009/03/30/do-you-see-with-you-
eyes-ears-nose-or-mouth/) \-- the main driver has been the ministry of
education AFAICT, & their motive seems to be to increase the level of exam
passes.

------
nonsequitur
The complete "Force Concept Inventory" test (PDF):
<http://shs.westport.k12.ct.us/physics/2007-2008/FCI-rv95.pdf>
<http://bit.ly/8YeiOZ> (mirror)

------
cpr
Greatly enjoyed the talk.

But, really, taking what he's doing to the limit (he even says so himself) is
just re-creating the Socratic method. (Though choosing the questions is hard
work, as he notes.)

And he can't do that, given his large class sizes (one of my classes at
Harvard was 700+ people, Ec 101 with Samuelson from MIT), so he uses this
peer-teaching approach to work around the limitation that he can't sit down
with a small group of them and work through the questions.

That's why we are sending some of our home-educated kids (those that show the
interest in and capacity for a rather intense education) to Thomas Aquinas
College in Ojai, CA.

It's probably the only school in the world that uses 100% Socratic method for
all courses (each no larger than 17 people), with no electives all 4 years,
outside of St. John's of Annapolis/Santa Fe (on which TAC is modeled to some
degree).

<http://www.thomasaquinas.edu> for those interested.

(Yes, it's an unabashedly Catholic school, but that doesn't diminish the
intellectual rigor in the least. It's also in one of the most beautiful spots
in the world, in the foothills of the mountains north of LA, near Ojai, which
is where the 50's film "Shangri-La" was made and which is still a spa/resort
area today.)

~~~
jbellis
> It's probably the only school in the world that uses 100% Socratic method
> for all courses

nice

> each no larger than 17 people

good

> with no electives all 4 years

wait, wtf?

I guess if their curriculum works for your kids, great, but one-size-fits-all
isn't a straitjacket I would have been interested in post-high school.

~~~
tokenadult
Phillips Exeter Academy

<http://www.exeter.edu/>

arguably has a more discussion-oriented approach to learning, definitely has
smaller classes, and has a rich supply of elective classes. And it's for high
school-age students rather than for college-age students. We are also a
homeschooling family, but we thought long and hard about sending our oldest
son to Exeter (which also has great financial aid) before continuing to
homeschool him. We may revisit the issue of how to do secondary education with
each of our other three children. Our oldest is now applying for colleges--
every college on his application list is a research university with strong
programs in mathematics and computer science (and, yes, lots of elective
course possibilities).

~~~
stcredzero
A little exposure to the "Lord of the Flies" might be good seasoning, provided
he's been given a few psychic defense lessons ahead of the time. (I was thrown
into the boarding school situation with _no defenses at all_ and had to cook
up my own. A little guidance would've been worth a lot.)

~~~
zackattack
Can you please elaborate about "psychic defense lessons" ?

~~~
stcredzero
I was very sheltered. I didn't know that I was allowed to swear, tell jokes,
or disagree with someone else before I got there.

~~~
tokenadult
Was "there" a school like Exeter or some other boarding school?

~~~
stcredzero
Military Academy

------
aaronsw
For people interested in this stuff, Howard Gardner's book _The Unschooled
Mind_ collects similar results from every discipline, from computer science to
history.

<http://books.google.com/books?id=DVB1n_KkYEQC>

For more on CS, of course, you'll want to read
<http://www.cs.mdx.ac.uk/research/PhDArea/saeed/paper1.pdf>

~~~
apu
I've been fairly skeptical of the Camel paper ever since reading Alan Kay's
rebuttal: <http://www.secretgeek.net/camel_kay.asp>

I trust Kay much more than these authors on matters of computer science,
teaching, or ideas in general.

------
Luc
Does anyone know what textbook he's referring to as the one he used as a base
for his original lectures? Sounds like 'Weidner and Selz', supposedly out of
print? <http://www.youtube.com/watch?v=WwslBPj8GgI#t=22m53s>

------
jmah
Slides here: <http://mazur-www.harvard.edu/sentFiles/MazurTalk_1516.pdf>

