Please pick up a
clicker!
By back door.
Transforming Teaching in a Physics Department:
Educational Reforms that Stick
Michael Dubson
Dept. of Physics
U. Colorado at Boulder
michael.dubson@colorado.edu
Boulder, Colorado
University of Colorado at Boulder
31,000 students
Physics Department
55 faculty
350 undergraduate majors
230 graduate students
Teaching at CU Physics
•  Teaching load = 1 course per semester
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All faculty rotate among as many courses as possible.
Few faculty are excused from big freshmen courses.
Prof teaches same course only 2 - 3X, before rotating out.
Freshmen courses taught by veteran/apprentice team.
Asst Profs must teach a freshmen course before tenure.
Among 35 departments at CU Boulder in A&S College,
Physics is ranked 1st in research …
and 1st in teaching.
Number of Physics Majors nearly tripled since 2001
Physics Education Research Group
University of Colorado at Boulder
• Physics faculty:
Noah Finkelstein
Steven Pollock
Michael Dubson
Kathy Perkins
Mellisa Dancy
( Carl Wieman )
•  PhET Team
10 employees
6 Postdocs
4 grad students
Collaborations with more than
a dozen faculty from other
departments.
http:// per.colorado.edu
Traditional Instruction:
teacher/student views compared
Freshmen course transforms since 1996:
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Concept Tests / Peer Instruction
Conceptual questions on exams
Online Homework (CAPA, Mastering Physics)
Physics Helproom
Washington Tutorials with undergraduate TA's
Pre/post tests to gauge effectiveness
Veteran/apprentice Team-teaching
PhET interactive simulations
Online Prelectures (U.of I. SmartPhysics)
•  All freshmen and sophomore classes transformed
•  Most junior/senior classes transformed
Peer Instruction/ Concept Tests,
Eric Mazur, Harvard 1997
Students are assigned to
Clicker groups to encourage/
enforce interaction.
A Difficult Question:
What Letter Am I thinking of?
A B C D E
Confer with your neighbors,
then vote.
A
A Sensitive Question:
•  If you were to significantly increase your
teaching efforts, how would this affect your
salary ?
A) Positively
B) Negatively
C) No effect
D) I don’t know or I don’t care
E) I don’t teach at all
A small block of mass m, starting from rest, slides down a frictionless
ramp to a round valley with radius of curvature R. At the bottom of the
valley (point A) the mass has speed v. What is the magnitude of the
acceleration of the mass when it is at point A?
A) g
B) (v2/R)
C) (v2/R)+g
D) (v2/R) - g
E) None of these
(g = +9.8 m/s2)
Students study for exams, so
put qualitative questions on exams,
questions that look like Concept Tests
Would you like to try a question about
A) static friction,
B) torque, or
C) DC circuits ?
A box of mass m is held stationary against
a vertical wall by a force of magnitude F
at an angle θ to the vertical. There is
friction between the wall and the box,
and the coefficient of static friction is µs.
The direction of the force of friction
exerted on the box by the wall is...
(A) up
(B) down
(C) zero
(D) not enough information given to
answer the question.
µs
m
θ
F
A toy car with mass m moves along
a massless wooden plank lying
horizontally over two support posts,
as shown. The car is rolling across
the bridge from point P2 to point P3,
(left to right). What can you say
about the magnitude of the net
torque (i.e. the sum of all torques)
about the point P1?
P1
(A) It is increasing.
(B) It is constant, and zero
(C) It is decreasing.
(D) It is constant, and non-zero.
(E) Not enough information is given.
P2
P3
Rank bulbs A, B, and C in order
of brightness from brightest to
V
dimmest.
A) A > B = C
B) A = B = C
C) A > B > C
V
D) B = C > A
E) None of the above
B
A
C
Simple technology works best
Too complicated
for all faculty
Too complicated
for some faculty
At U.Colorado Boulder,
28,000 students have registered clickers,
used in >200 courses in >20 departments.
Clicker use started in physics 1997,
slowly spread to other departments
Ease of Clicker Use at CU
Clicker ID is part of CU student ID.
Students register their clicker once online.
Faculty get clicker roster with class roster.
Clicker use spread to other departments
(Science Education Initiative created by Carl Wieman,
supported by CU Administration).
⇒ Almost all students own clickers,
⇒ Low activation energy for Clicker adoption
Poor use of clickers..
•  solely for taking attendance
•  for quizzes or high-stakes testing
•  only occasionally, or at set times
Better use of clickers..
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Integrated into lecture, frequent
Require peer instruction
Mix of difficulty: very easy to very difficult CTs
Generous credit for any answer
Low grade impact (~2%)
Worse Concept Tests
•  merely test recall
•  blind application of formula/recipe
•  many numbers
Better Concept Tests
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qualitative understanding
students provide next step in the lecture
use familiar skill in unfamiliar context
support a learning goal
How do you make up good
Concept Tests?
•  Key points in lecture ⇒ make with CT
Don't tell. Ask.
•  What is my learning goal? Test with CT
•  Listen in on student-student conversations
in the Helproom.
•  Best of all: go to http://per.colorado.edu
Giving the answer STOPS discussion
•  Elicit student reasoning, before giving answer.
•  Understanding why wrong answers are wrong is as
important as why right answers are right.
•  Value reasoning above answer. A right answer
without a reason is useless. A wrong answer for a
good reason has value.
Student must be convinced that
•  understanding = high exam score.
•  memorizing answers to specific questions
= low exam score.
Freshmen Physics at CU
800 students,
2 faculty = 1 veteran / 1 apprentice
10 graduate TAs, 10 undergraduate TAs
3 Lectures , 1 Recitation per week
Lecture = 300 students / 1 faculty,
Recitation = 28 students / 2TAs
•  50 min lecture:
Clicker question running when students enter
~ 20 min lecture in 10 min chucks
~ 30 min on 6 or 7 concept tests, discussion, demonstrations
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Required pre-lecture online (Illinois SmartPhysics)
Weekly homeworks : 70% quantitative, 30% qualitative
Exams: 40% quantitative, 60% qualitative/conceptual
Students bring own formula sheet to exams.
Quantitative vs. Qualitative Problems
• Quantitative:
In the circuit, V = 25V, R1 =
R2 = 10Ω, R3 = R4 = R5 =
15Ω, R6 = 50Ω. What is the
current through resistor R3?
Qualitative.
When R6 increases, the current through R3 _______.
A) Increases B) decreases C) remains constant?
Physics HelpRoom
•  All TA's and faculty hold office hours here.
•  Hours staggered, room is always staffed.
Tutorials in Introductory Physics
U.Washington PER group
Recitation Sections in Physics 1, 2
•  28 students, 2 TA’s
•  Students work in groups of 4
•  TA’s do not lecture
•  TA’s do not give answers
Washington Tutorials
replacing traditional TA-led recitations
Success required:
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Dedicated space / furniture
Lab equipment
Undergraduate TA's
Proper training of staff
Assessment is essential
Standardized Pre/post tests:
Physics 1 Mechanics: FCI, FMCE,
Physics 2 E&M: BEMA
An astronaut in intergalactic space is twirling a rock on
a string. Suddenly the string breaks when the rock is at
the point shown)
D
C
A
B
Which path (A, B, C, or D) does the rock follow
after the string breaks?
Force Concept Inventory (FCI) pre/post test
traditional lecture
interactive engagement
<g> = post-pre
100-pre
R. Hake, ”…A six-thousand-student survey…” AJP 66, 64-74 (‘98).
Assessment is essential.
Standardized Pre/post tests:
Physics 1 Mechanics: FCI, FMCE,
Physics 2 E&M: BEMA
Force Concept Inventory
(FCI) Pre/Post test scores,
BEMA (matched) (CU scoring) Fa04
Algebra-based 1st-Semester,
Fall 05
g(ave)=.44, N=331
CU upp LA 1120
LA
TA
TA
50
Hake gain G = 0.494
div post pre post
post pre
post
45
Pre
40
# of students
50
Frequency
40
30
Post
35
30
25
20
15
10
20
5
0
10
0
6
12
18
24
30
36
42
48
54
60
66
72
78
84
90
96
Score (%) (CU scoring)
0
0
2
4
Pre (ave=26)
6
8
Post (ave=59)
10
NCSU trad
12post14
NCSU honor
CMU M&I
16& CMU
18trad20 post22
Score
post
CMU upp
div post
24
26
28
30
Problem: Good CTs lead to good
class discussion, eats into lecture time
Solution:
Stop complaining.
Avoid long derivations in lecture:
•  Create HW problems that test knowledge of derivations.
•  Show detailed derivations online or in assigned reading.
•  Derive in class only if making point testable with CTs
The Golden Rules of Lecture:
Rule 0.
Don’t reinvent. It’s too much work.
Faculty are much more likely to try something new,
if it doesn’t involve extra work.
Go to http://per.colorado.edu.
The Golden Rules of Lecture:
Rule 1.
It's OK to lecture less,
because they're not listening anyway.
(Scribe mode ≠ listening)
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Use Concept Tests & Peer Instruction
Active learning works, passive learning does not.
Lots of demos, tied to Concept Tests
Brief derivations, tied to Concept Tests
Put lecture notes (+ everything else) on the Web.
SmartPhysics Prelectures
Rule 2.
Morale is vital:
Talk to / listen to students, in lecture, in office
hours, in the Helproom.
Feedback from students is essential.
If they learned something, but they leave
hating the subject, you have failed.
Common demominator of poor teaching:
Teacher/Student disconnect
Rule 3.
Emphasize qualitative reasoning and
conceptual understanding.
•  in lecture
•  on homeworks
•  especially on exams
It doesn't matter if they can compute the acceleration,
if they don't know what acceleration is.
The stubborn persistence of
incorrect student beliefs :
•  Aristolean thinking
•  Belief that learning means memorizing.
A) FT > µK mg
B) FT > µS mg
C) FT = µK mg
D) FT = µS mg
C) None of these must be true
Clickers use in upper-­‐division CU physics 04
Term
05
06
07
08
09
S F S F S F S F S F S
Mech Math I
✔
✔
Mech MathII
✔
✔
EM I
✔ ✔
EM II
✔
QM I
✔ ✔
QM II
✔
Stat Mech
✔
✔
✔ ✔
✔ ✔
Solid State
✔
✔
Plasma
Nuclear/HE
10
F S F
✔
✔
✔ ✔
✔ ✔
✔
✔
✔ ✔ ✔
✔
✔ ✔ ✔
✔
11
S F
✔ ✔
✔ ✔
✔ ✔
✔ ✔
✔
✔
✔
A ball rolls back and forth in a valley. Eventually, the ball
slows and stops. We never observe the reverse.
Consider :
•  Conservation of energy (1st Law of Thermo)
•  Entropy of an isolated system increases (2nd Law)
•  Conservation of momentum
The reverse process never occurs because this would violate:
A) 2nd Law only
B) All three
C) Cons. of energy & cons. of mom.
D) Cons. of energy & 2ndLaw
E) Cons. of mom. & 2ndLaw
An unopened bottle of Champagne, equipped with
a pressure gauge, has been sitting on the shelf
for a long time. The bottle is given a brief,
vigorous shake. What happens to the pressure
in the bottle? (A brief shake will raise the
temperature < 0.01o C)
A) The pressure remains unchanged
B) The pressure falls significantly.
C) The pressure rises significantly.
The ground state energy of a finite square well is
______ than the grd state energy of the infinite
square well with the same width a
A) the same
B) higher
C) lower
?
a
a
Why did clicker use spread to upper div classes?
•  Concept Test libraries available.
•  Ease of clicker use.
•  Popular with students.
•  Faculty trained in freshman classes.
•  What’s missing from this list?
What does learning look like?
Students debate a concept test
•  Concept Tests "
•  Modified Homework"
•  Homework Help Sessions
•  Weekly 1-hr Tutorials
Upper-Level Course Transformation"
Transforms that stick
Necessary Conditions:
•  Strong support from the top.
•  Hard work from the bottom.
•  Acceptance from the middle.
Never pressure faculty. Build consensus first.
Respect traditional lecturers.
“People don’t disagree with their own
ideas”
Train new faculty as they arrive.
Provide complete resources for receptive faculty.
Collect evidence that transforms improve learning.
Reforms stick if seen as valuable by students and faculty.
Two-way conversations with students are vital,
because students can misinterpret what we say.
“Pearls Before Swine” by Stephan Pastis, 2002.
Concept Test Libraries available at
http://per.colorado.edu/ctl