Transcript Classic Research Articles as PBL Problems Hal White Dept of Chemistry and Biochemistry University of Delaware Case Study Teaching in Science 7 October 2005 Buffalo, NY.

Classic Research Articles
as PBL Problems
Hal White
Dept of Chemistry and Biochemistry
University of Delaware
Case Study Teaching in Science
7 October 2005
Buffalo, NY
Introductory Science Courses
Stereotype
1. Lecture format that is content-driven.
2. Abstract concepts introduced before concrete
examples.
3. Enrollments typically more than 100.
4. Limited student-faculty interaction.
5. Grading based on a few multiple choice
examinations that emphasize recall of information.
6. Reinforce intellectually immature students to a
naïve view of knowledge.
What do we teach in science?
“Much of our educational system seems
designed to discourage any attempt at
finding things out for oneself, but makes
learning things others have found out, or
think they have, the major goal.”
Anne Roe (1953)
Common Features of a
Problem-Based Approach to Learning
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Learning is initiated by a problem
Problems are based on real-life, open-ended
situations.
Students identify and find the information
necessary to solve the problem using appropriate
resources.
Students work in small permanent groups with
access to an instructor.
Learning is active, integrated, cumulative, and
connected.
Overview
• The Case for Classic Articles as PBL
Problems
• Example of an Article-Based Course
• Experience a Classic Article Problem
• Designing a Course Around Classic
Articles
• Student Response
Characteristics of Good PBL Problems
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Engage interest
Require decision and judgement
Need full group participation
Open-ended or controversial
Connected to prior knowledge
Incorporate content objectives
Classic Articles as PBL Problems
Advantages
• Authentic (not contrived)
• Complex
• Relevant to the Discipline
• Introduce Important Historical Figures
• Encourage use of Library
Science as Literature?
“There is no form of prose
more difficult to understand
and more tedious to read that
the average scientific paper.”
Francis Crick (1995)
Science as Literature?
“I am absolutely convinced that science
is vastly more stimulating to the
imagination than are the classics, but the
products of this stimulus do not normally
see the light of day because scientific
men as a class are devoid of any
perception of literary form”
J. B. S. Haldane
What is a Classic Article?
“It is indeed rare for a scientific paper to
remain central to current concerns several
decades after its publication; in general,
papers decay like last winter’s leaves or
this summer’s pop songs, and scientists
instead cite the latest review paper.”
Edward Ahrens (1992)
How can we connect students to
their discipline?
“Only by understanding the difficulties
encountered in trying to do what now seems
simple can a student appreciate the hurdles
which must be surmounted in modern
experiments of which we, for the most part,
hear only the conclusions”
James Bryant Conant (1946)
Introduction to Biochemistry
Evolution of the Course
1970's Course for non-science majors
based on Herman Epstein’s model.
1989 Modified course initiated as part of a
new B.S. Biochemistry curriculum.
1993 Problem-Based Learning format
introduced.
1996 Undergraduate Tutor-Facilitators
used for the first time.
Introduction to Biochemistry:
An Article-Based PBL Course
• 3 Credits, No Laboratory, 8:00 AM MWF
• Theme - Hemoglobin and Sickle Cell Anemia
• First Biochemistry Course for Sophomore
Biochemistry Majors
• Required for the Major
• Taught in a PBL Classroom
• Enrollment 20 - 35
• Uses Juniors and Seniors as Group Facilitators
Introduction to Biochemistry
Course Description
• Heterogeneous groups of 4 discuss and work to
understand about ten classic articles.
• Articles presented in historical context, show the
development of scientific understanding of
protein structure and genetic disease.
• Assignments and examinations emphasize
conceptual understanding.
• Instructor monitors progress, supervises tutors,
presents demonstrations, and leads whole class
discussions to summarize each article.
Introduction to Biochemistry
Instructional Goals For Students
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Become intellectually independent learners
Recognize and confront areas of personal ignorance
Review and apply chemical, biological, physical, and
mathematical principles in a biochemical context
Improve problem-solving skills
Create, understand, and value abstract biochemical models
See biochemistry in relevant historical and societal contexts
Discover and use the resources of the library and the Internet
Gain confidence in reading and understanding scientific
articles
Experience the powers (and pitfalls) of collaborative work
Appreciate importance of clear oral and written communication
Learn to organize logical arguments based on evidence
Oxidation and Reduction of
Hemoglobin
CHEM-342 Introduction to Biochemistry
Constructing Meaning
from Stokes (1864)
• What was done? Read Section 11 of the Stokes article. In the
left-hand column of the work sheet, transform Stokes’ description
into a multi-step protocol suitable for an undergraduate chemistry
laboratory experiment.
• What was seen?
In the middle column, describe what
observations students would make.
• What happened chemically? In the last column, explain briefly
in words the chemical basis for the observations.
• How do we represent it? On the back of the work sheet,
construct a diagram (model) that represents the chemistry.
Transforming Section 11 of Stokes’
Article into a Laboratory Experiment
Procedural
Step
1.
2.
3.
4.
5.
6.
Expected
Observation
Chemical
Meaning
Question for Group Work on
Midterm Examination
Prof. Essigsaure returned to his lab one night to prepare for a lecture demonstration
based on the experiment presented in the second paragraph of Section 11 in
Stokes’ 1864 article. Within minutes he was looking high and low for the
glacial acetic acid and mumbling angrily about associates who don’t replace
the things they use up. Frustrated, but undaunted, he figured any acid would do
and substituted concentrated hydrochloric acid. After all, he reasoned, a
stronger acid should work even better. — Not so. Sure enough the
hemoglobin solution turned brown immediately upon addition of HCl but,
much to his initial puzzlement, the resulting hematin did not extract into the
ether layer.
Explain in chemical terms why HCl cannot be substituted for glacial acetic
acid in this experiment. Draw chemical structures and diagrams to
support your argument. If you are uncertain of the explanation, please
outline the possibilities you have considered or how you analyzed the
problem.
Constructing Models
to Explain Observations
O2 (g)
Air
1. Diffusion, slow transfer
Water
2. Shaking, rapid transfer
O2 (l)
HbO2
Reversible binding, rapid
H2 O
SnIV
Hb SnII
Irreversible oxidation, slow
Introduction to Biochemistry
Student Assignments
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Write an Abstract
Construct a Concept Map
Draw an Appropriate Illustration
Critique from a Modern Perspective
Find out about the Author
Explore a Cited Reference
Introduction to Biochemistry
Student Perceptions 1995-2004
A. Consider items 1 through 12 and rate them with respect to how important
they are for success in CHEM-342, Introduction to Biochemistry.
(1 = Extremely Important to 5 = Not Important; N = 263 out of 268)
Item
1. Personal Initiative
2. Library Research
Skills
3. Taking Notes in Class
4. Writing Skills
5. Collaboration with
Classmates
6. Oral Communication
Skills
Mean
± SD
1.47
± 0.61
1.88
± 0.80
2.92
± 1.00
2.16
± 0.85
1.55
± 0.76
1.77
± 0.81
Item
7. Prior Knowledge
8. Memorization
9. Learning New
Information
10. Problem Solving
Skills
11. Conceptualization
12. Attendance
Mean
± SD
2.83
± 0.97
3.90
± 0.95
1.61
± 0.77
1.64
± 0.79
1.50
± 0.65
1.43
± 0.69
Introduction to Biochemistry
Student Perceptions 1995-2004
B. Consider the items 1 through 12 in relation to other science courses.
Circle those items which, in your experience, are more important in CHEM-342
than in most other science courses you have taken. (N=263)
Item
Percent
Item
Percent
1. Personal Initiative
40.8
7. Prior Knowledge
12.1
2. Library Research
Skills
3. Taking Notes in
Class
4. Writing Skills
60.0
8. Memorization
1.1
1.9
9. Learning
New Information
10. Problem Solving
Skills
14.8
5. Collaboration with
Classmates
6. Oral Communication
Skills
72.7
11. Conceptualization
40.5
57.8
12. Attendance
39.7
37.5
46.9
Effect of Facilitators on Attendance
Attendance before facilitators: 91.1%
Attendance after facilitators: 94.1%
(32% reduction in absences)
Allen & White (2001). In, Student-Assisted Teaching,
Miller, Groccia & Miller, Eds. Bolton, MA: Anchor.
Effect of Facilitators on Effort
Hours before facilitators: 4.8 per week
Hours after facilitators: 6.0 per week
(25% increase in time spent on course
work outside of class)
Allen & White (2001). In, Student-Assisted Teaching,
Miller, Groccia & Miller, Eds. Bolton, MA: Anchor.
Learning Issue Matrix
Course
Course
Course
Objective Objective Objective
No. 1
No. 2
No. 3
Article
No. 1
XXX
Article
No. 2
XX
Article
No. 3
X
XXX
Course
Objective
No. 4
X
X
XXX
X
X
XX
Prelude to the Final Exam
Always remember that it is possible to
be a worthwhile human being
regardless (or in spite of) how much
biochemistry you know. This won't
necessarily help you with biochemistry,
but it may help you keep your sanity.
Hiram F. Gilbert (1992)
Course Web-Site
Introduction to Biochemistry
www.udel.edu/chem/white/CHEM342.htm