Interactive simulations for teaching
physics
Work supported by: NSF, Hewlett Foundation, Kavli Foundation,
Univ. of Colorado, me and Sarah
 Physics Education Technology Project (PhET)
Develop interactive simulations
Research on simulation design and effectiveness
When simulations carefully tested and refined :
•Highly engaging
•Very effective for learning
•Work with very wide range of students
(“grade school to grad school”)
Goals for talk
Examples of good simulations
Little about research on what makes them useful
 principles to keep in mind when using.
show website, sim list, balloons and sweater, moving man, elctromag
PhET (phet.colorado.edu)
•~ 60 interactive simulations
•Intro physics, modern physics, some chemistry, bit of math,
starting to expand into geo and bio, …
•Phet-based activities database on website--Trish Loeblein
run phet sims (all free!):
• directly from web (regular browser, platform independent)
• download whole website to local computer for offline use
2006-- 1 Million sims launched off website;
50,000 full site downloads
Extensive development and testing process--teams
(faculty, software engineers, sci. ed. specialists)
Physics faculty:
Michael Dubson
Noah Finkelstein
Kathy Perkins (manager)
Carl Wieman
Phet Staff
Postdocs:
Sam McKagan
Linda Koch (Chem)
Software Engineers:
Ron LeMaster
Sam Reid
Chris Malley
Michael Dubson
Grad students:
Wendy Adams
Danielle Harlow
Chris Keller
Noah Podolefsky
HS Teacher:
Trish Loeblein
~6 full time equivalents
Staff:
Mindy Gratney, Linda Wellmann
Design Features and Criteria
• Engaging and productively fun
(interface design, appearance, …)
• Connection to real world
• Highly interactive- stuff happening, user controls
• Explicit visual & conceptual models (experts’)
• Explore and discover, with productive constraints
• Connect multiple representations
K.K. Perkins, et al, “PhET: Interactive Simulations for Teaching and Learning Physics”,
Physics Teacher (Jan 2006)
Most important element--testing with students
1. Think aloud interviews
(~200 hours)
Explore with guiding question
surprisingly consistent,
always revealing
2. Observations of use in lecture, recitation and lab,
homework solving sessions.
Example- of what
revealed by interview
studies.
Radio waves.
Initial startup.
Experts- - really like.
Students--Watch without interacting. Don’t like.
Misinterpret.
Start with curve view, manually move electron.
Very different result.
Later move to full field view, manipulate, like, and understand.
Correctly interpret.
Why do you think starting this way works so much better?
briefly discuss with neighbors, then will collect ideas
Why starting this way works
so much better?
Why starting this way works
so much better?
Matches research on learning.
•Cognitive demand. Novices don’t know what to focus on.
treat everything equally important. Much more than short-term
working memory can handle, overwhelming
• Construction of understanding.
Other important features:
Visual model-electrons in transmitting and receiving antennas,
display of waves
Interactivity
Example illustrates important principle:
students think and perceive differently from experts
Good teaching is presenting material so novice students
learn from it, not so looks good to experts!
Violated by most simulations
(and many lecture demonstrations, figures in texts,…)
PhET sims almost never right the first time.
Test and modify to get right.
Simulation testing microcosm of education research
Routinely see examples of principles established in
very different contexts.
•cognitive load
•construction of understanding
•build on prior knowledge
•connections to real world
•exploration and deep understanding  transfer
•motivation--factors affecting and connections to learning
•perceptions based on organizational structures,
structures change and develop, changes perception.
•…
Sims useful in variety of settings
Pre-class or pre-lab Activity
Lecture/classroom
Visual Aids, Interactive Lecture
Demos, & Concept tests
Labs/Recitations
Group activities
Homework
Need some structure--activities database
advice and workshops Trish Loeblein
ploeblei@jeffco.k12.co.us
bits of examples of effectiveness in different settings
show wave on string
Lecture (Non-science Majors Course)
Standing waves-- Sim vs. Demonstration
Wave-on-string sim vs Tygon tube demo
Follow-up Concept Tests:
A
B
C
snapshots at
different times.
1. When the string is in position B, instantaneously flat,
the velocity of points of the string is...
A: zero everywhere.
B: positive everywhere.
C: negative everywhere. D: depends on the position.
Correct :
2002 demo: 27%
2003 sim: 71%
2. At position C, the velocity of points of the string is... Correct :
A: zero everywhere.
B: positive everywhere.
2002 demo: 23 %
C: negative everywhere. D: depends on the position.
2003 sim: 84%
Features that make a differenceexperts hardly notice, BIG difference for novices
1. Green beads on string that show moves up and down,
not sideways.
2. Speed set so novice brain can absorb and make
sense of it.
3. Can do controlled changes, most in response to student
requests. Sort out what makes a difference and why.
What else does simulation provide over usual figure and
explanation in lecture or textbook?
1. see direct cause and effect relations
2. explicit visual models
example-electromagnet, friction, gas, cck
Standard Laboratory
show cck
(Alg-based Physics, single 2 hours lab):
Simulation vs. Real Equipment
Circtuis
Exam
Questions
DC DC
Circuit
Final
Exam
Questions
Fraction Correct
1
0.9
CCK (N =99)
0.8
TRAD (N=132)
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
q1
q2
q3
Question
cntl
p < 0.001
N D. Finkelstein, et al, “When learning about the real world is better done virtually: a study of substituting
computer simulations for laboratory equipment,” PhysRev: ST PER 010103 (Sept 2005)
f. A few important interface characteristics*
• Intuitive interactivity vital
• Controls Intuitive when most like hand action
– Grab-able Objects
– Click and Drag
– Sliders to change numeric values
• Representations
– Cartoon-like features  scale distortion OK
– Good at connecting multiple representations, but
proximity and color coding helps (energy sktprk)
*more than want to know in Adams et al. papers
Conclusions:
Interactive simulations powerful new technology for learning
science. But not automatically good.
Trish Loeblein
ploeblei@jeffco.k12.co.us
Phet.colorado.edu
booth in APS show- play with, discuss.
references on website under “research”
Surprising differences in motivation and learning
engaged exploration vs. “performance mode”
Before topic covered in classactively interested and engaged in figuring out  answer
After covering in class (same students, same topic!)
struggle to remember what told or read, not use sim to explore
and figure out, even with repeated encouragement!
Frustrated and unsuccessful!
(ed. research microcosm cont.--matches perfectly with results
of Dweck psychology studies- “performance mode” )
General results from student interviews*
1. Think aloud interviews
(~200 hours)
Explore with guiding question
a. Surprisingly consistent responses, particularly on interface.
b. Vocabulary very serious hindrance to learning and
discussion-- see because simulation removes
c. Animation attention, but not thinking.
Interactivity thinking & learning.
W. K. Adams, et al. , A Study of Educational Simulations Part I - Engagement and
Learning., A Study of Educational Simulations Part II - Interface Design.,
PhET’s Checklist for creating
Effective Sims and Tutorials/Activities
Is Sim or Activity ….
1) Aligned with learning goals?
2) Aligned with current research?
3) User-tested?
•
•
•
•
Ease of use
Correct Interpretation
Engagement
Achieves learning goals
Interesting results from interview studies* (cont.)
d. the good, the bad, and the evil sim
Good sim is extremely effective for wide range of
students: understand difficult concepts, can explain &
apply to real world situations.
Bad sim- very little learned.
Awkward distracting interface, boring, confusing.
Evil sim--effective at teaching wrong things!
e. Student testing critical! Interviews always reveal
undesired perceptions or distractions in first versions!
many other examples of power of visual models
all of quantum! (S. McKagan)
quantum wave interference
lasers
Stern-Gerlach
MRI
major impact on student thinking
tunneling
…
Rethinking how intro quantum
mechanics should be taught.
Key missing element.
Some general principles revealed for how people learn
physics
•Cognitive load important--too much stuff overwhelming,
Build up slowly works well. (Radio waves full view)
•Need to connect to prior thinking-- start using familiar
elements (tire pump in ideal gas), build understanding
•Visual models vital (balloon and sweater, CCK,QM, …)
•Absorb and make sense only when ask questions
and then seek answers.
Animation without interactivity draws attention, but not
exploration and understanding.
•Text and explanations usually ignored or misinterpreted
unless seeking that particular point.
Integrating a sim on a topic (Lect. & HW)
(Photoelectric Effect in Modern Physics) (S. McKagan, to be pub.)
Univ. of Wash.:
• Student learning of photoelectric effect deficient
• Developed & used Photoelectric Tutor (PT)
Exam Q: What would happen to current reading if you:
Q1: Changed metal. Why?
Q2: Double intensity of light. Why?
Q3: Increased DV across electrodes. Why?
% Correct
show photoelectric
effect
CU:
Incorporated sim
Course
Q1
Q2
Q3
N
UW w/o PT
UW w/ PT
65
75
40
85
20
40
26
36
CU Fa05
CU Sp06
91
86
87
88
85
84
189
182
Visual Models
Development Process
Team for each sim
faculty content expert(s)
sci. ed./user expert(s)
software engineer
Learning
Goals
Initial Design
~Final Design
Research Base
Classroom
Use
Interviews
Redesign
b
Interviews
Initial Design &
General Approach
Research base:
• Ed. Psych / Cog. Sci: How people learn
• Educational Software Design
• Student Conceptions in Physics
• PhET research findings
Assessment of Design:
• Usability – easy/intuitive
• Interpretation – correct/productive
• Engaged exploration
General
Design
Guidelines
• Can students construct understanding of
main ideas? Achieve learning goals?
Thorton and Sokoloff, 1997
+
0
time
-
Velocity
Demo 4:
Sketch position vs time and
velocity vs time graphs for
when Moving Man:
walks steadily towards the
tree for 6 seconds,
then stands still for 6
seconds, and
then towards the house twice
as fast as before for 6
seconds.
Position
Lecture – Interactive Lecture Demos
+
0
-
time
0
time
Position
Position
+
A
Position
time
5s
10 s
15 s
20 s
+ C
0
Velocity
0
time
Position
Velocity
+
time
+
0
-
time
5s
10 s
15 s
20 s
+ D
0
time
-
+
0
time
5s
10 s
15 s
Velocity
Velocity
-
-
0
-
-
-
+
B
20 s
+
0
-
time
5s
10 s
15 s
20 s
Lecture – Concept tests
Electromagnetic
waves:
Radio Waves sim
Concept Tests
and
Peer Instruction
The speed of the wave (signal) is measured as…
a.how fast this peak moves to the right.
b.how fast this peak moves up and down.
c.could be a or b
Incorporating a suite of sims
(Modern Physics for Engineers)
~ 10 interactive simulations in lecture and homework
(clickers, real life applications, conceptual homeworks)
Quantum Mechanics Conceptual Survey
Course
Reformed
with sims
Traditional
normalized
Post
gain
65
0.50
Eng. Sp06
Pre
30
N
156
Eng. Fa05
Eng. Sp05
Phys. Sp06
Phys. Fa05
32
(30)
44
40
69
51
64
53
0.55
0.30
0.36
0.21
162
68
23
54
Phys. Sp05
(44)
63
0.33
64
Interactive Recitation Study
Reformed large-scale introductory
calculus-based physics course with Tutorials
vs.
“CCK” (N=180)
“Real” (N=185)
Keller, C.J. et al. Assessing the effectiveness of a computer simulation in conjunction with Tutorials
in Introductory Physics in undergraduate physics recitations,", PERC Proceedings 2005
Interactive Recitation Study
DC Circuit Q's on Midterm Exam
1
CCK
Real
0.9
Fraction Correct
0.8
0.7
p=0.01
0.6
0.5
0.4
0.3
0.2
0.1
0
3
4
8
12
13
14
Avg
Questions
but end of semester exam, no observable difference