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Re: [Phys-l] Students' READING abilities



One of the thing that Modeling does is change the labs so that the students
have inquiry, but are trained to do specific things to investigate the
physical situation. They are initially given a structure where they must
first graph the raw data. They they must make a modified graph to
investigate the functional dependence. Finally from the modified graph they
must write the final equation. This is spelled out at the beginning and
they are given a handout to help them do it correctly. They also have an
initial practice lab where they are guided to do it correctly.

After that, they are not given specific lab writeups, but they must follow
the rubrics laid down at the beginning. All labs initially start with
identification of variables, and then they have to do the labs starting with
just their notes, and graph paper, or lab book. They are NEVER told what
functional dependence to expect, and they have not had any theory initially.
Following this the theory can be developed in a mini-lecture. The lab
writeup is written outside class, and has a reasonably large grade attached
to it. Grading is very picky and students have to have correct graphs with
correct units. So if the original graph is X vs t, and the final graph is X
vs t^2 the units must be s^2, and the grading is according to a set rubric
which specifically mentions correct scales, units...

Many years ago it was common to introduce the idea of modified graphing in
HS chemistry, and continuing to do it routinely in HS physics. But this has
in general gone away. The Modelers feel that this is an excellent method of
analysis and helps understanding. The FCI scores achieved by Modeling are
fairly good, so this practice may be beneficial.

Notice that Modeling has both inquiry, but some strict grading requirements.
Students are first given concrete preparation, but they also are required to
work in groups, and outside class. I think that as you make things easier
by being extremely explicit for each item, students tend to think even less.
Modeling provides a fairly good balance between explicit instructions and
freedom to explore. During the in class lab the instructor uses Socratic
dialog to help the students do it correctly, but they are on their own for
the writeup. Of course if they come to separate "office hours" you use
Socratic dialog to help them with the writeups. And students who say that
their partner is sick so the graphs are missing, get a lower grade. The
basic lab is graded for the whole group of 3, but conclusions are
individual, so grading enforces both group and individual work. Identically
written conclusions can have lower grades.

There is firm evidence that inquiry classes improve the thinking skills of
students, while conventional "rigorous" classes do not. This was shown in
the ancillary material for the recent Science article. But inquiry can be
quite guided, and can involve some very strict grading. The Modeling lab
grading rubric is actually quite simple and does not involve excessive time
for the grader.

Following the lecture part of the lesson, students work problems outside
class, and are assigned problems to publicly present to other in class. At
this point there is another grading opportunity. Presentation is not
optional, and all must present, in small groups. Sometimes some class time
can be spent on getting them started solving problems, but work outside
class is required. During the verbal presentations, it becomes obvious who
understands, and who just copied. Refusing to present can result in a low
grade. So inquiry does not mean no outside work.

Inquiry is often painted as being unstructured, and nebulous. But it can
also be set up using some strict rubrics. The Workshop Physics inquiry has
students doing labs outside of class time. WP has detailed writeups that
must be followed. But within these writeups students still have to make
many decisions themselves. Real Time Physics has most of the inquiry in the
lab part of a course, and again has detailed writeups similar to WP. The
grading is generally done on the homework which mirrors the labs, and can be
turned in without discussion. Grading is easy because it often involves
just looking at the graphs students have drawn. And failure is always an
option. Hake's Socratic Dialog Labs require students to repeat the labs
until they get it right!!! This requires a dedicated lab.

But the essence of inquiry is that students NEVER get the theory before the
lab. First they see the concept in action, and then the theory is discussed
in a lecture or in a required reading. Actually the same labs are often
done as in traditional classes, but just turned around. RTP and WP
integrate some theory in the lab writeups after the students have done the
exploration.

Yes, students don't like to read, but according to my wife who works with
lawyers, lawyers do not read accurately either. You have to underline and
boldface the relevant things. Part of the problem is that textbooks do this
all the time frequently within the body of the text. I think this practice
has made students lazy readers. While it produces some improvement at
comprehension when you first start doing this, it probably has the effect of
making readers lazier in the end.

You have to have students give some written responses and explanations.
This helps them become better writers and readers. And they have to be
graded strictly. I would not necessarily grade on spelling as long as it is
understandable, but grammar that makes the meaning unclear should call for
penalties. Written responses also are often much more revealing of what
they understand than just doing problems.

John M. Clement
Houston, TX



I just got done grading and handing back lab reports in which students
took some measurements of A as a function of B, and the expected
relationship is A is porportional to B^2.

In past years the lab handout stated the students should construct a
graph of A as some function of B that would allow them to make a
convincing argument that the theortetical prediction is valid.

Of course I expected them to plot A versus B^2, and get a reasonably
straight line, and comment on that in their conclusion. Of course what
I got was all over the map.

I got so tired of poor reports that I changed the handout so it now
says. "Plot A versus B^2 and see if you get a straight line as the
theory predicts. Remember this means plot A as a function of
B-squared." But results were still all over the map.

When I talked individually to students about why they didn't do what the
directions stated, I got a variety of responses that support what Tim
and Rick have already mentioned. In no particular order, here are some
responses:

(1) Oh, I don't read the lab handouts because I can never understand
them. I just ask someone else in the class what we're supposed to do.

(2) I did read the handout, and it didn't make any sense to me, so I
just used my own judgment about what we were supposed to do. [Which
might not be so bad if the student took the time to develop some good
judgement about the goal of the experiment and how one might reach that
goal.]

(3) I thought I did plot A versus B^2. [The student had plotted B^2
versus A because s/he didn't understand the language. One third of the
class plotted (some function of B) versus (A) rather then (A) versus
(some function if B). This ocurred even though time and time again I
have told them that A as a function of B means the same thing as A
versus B, and these mean A on the vertical axis and B on the horizontal
axis.]

Conclusions:

Many students don't read. Many students can't read critically and
understand what is written. Students don't listen. Students would
rather copy someone else in the class. I have office hours, but
students won't come to office hours to ask questions.

John Clement said, "One needs to change the conventional structure to an
inquiry mode with frequent communication between students, and students
and teacher."

You can't do this if students refuse to do anything outside of class,
because in-class time is way too short for accomplishing the goals of
the course. It goes back to something I've said before: I expect
students to read assignments outside of class. I expect students to do
experiments outside of class. I expect students to write outside of
class. I expect students to solve problems outside of class. I expect
students to come to office hours if they have questions. But today's
students think I am totally unreasonable. If I can't teach them what
they need to know about physics within the contraints of five 50-minute
class periods a week for 30 weeks, then I must be a lousy teacher. They
don't have any more time to spend on physics than class time. Since
they have become accustomed to teachers that don't demand out-of-class
work, they can't read, they can't write, they can't solve problems...
because they don't have any practice doing these things. And they fill
their out-of-class hours with sports, TV, socializing, etc. and think it
is an unreasonable intrusion if I want them to spend some of that time
doing physics.

The proponents of inquiry mode appear to mean "inquiry mode in class
only." For a 5-credit class I want 15 hours per week of inquiry mode...
Some of it during class, some of it during reading, some of it during
writing, some of it during labs. I'm lucky if I can just get them to
class for all 5 class sessions.

I agree different teaching methods can have an effect on learning, but
it's hard for any method to have success if the students aren't willing
to spend the required time. You learn to read by practicing. You learn
to write by practicing. You learn to shoot free throws by practicing.
No problem there. If students would spend 10-20% of the time on physics
that they spend practicing their sport, I wouldn't be complaining.