ADDRESSING THE NATIONAL NEED FOR NEW LABORATORY EXPERIENCES IN PHYSICS
Ben ZwicklHeather Lewandowski
Noah Finkelstein
University of Colorado, Boulder
PER@C
Graduate studentsStephanie BarrBen Van DusenKara GrayMay LeeMike RossBenjamin SpikeBethany Wilcox
Really Recent PhDsLauren Kost-Smith
FacultyMelissa DancyMike DubsonNoah FinkelsteinHeather LewandowskiValerie OteroKathy PerkinsSteven PollockCarl Wieman (on leave)
Post-docsCharles BailyDanny CaballeroStephanie ChasteenLaurel MayhewAriel PaulRachel PepperNoah PodolefskyBenjamin Zwickl
The genesis of the project
Junior FacultyAMO Physics/JILA
HS
PhD, Yale
Instructor
Post-doc
BS
THE NATIONAL CALL
ONE MILLION…
…more STEM graduates in a decade!
The Gist
1. Keep USA economically competitive
2. Need a million additional STEM degrees over decade
3. Improve retention during first 2 years.
5 Recommendations
1.Adopt validated effective teaching practices.
2.Do research and design oriented lab courses
3.Fix the math gap.
4.Link new STEM graduates with new STEM jobs.
5.Create a Presidential Council on STEM Education
Also includes:More undergraduate research experiences
Grassroots efforts
• 100’s of professors and instructors• Innovating at the upper-division labs• 4 year lab curriculum
How can we respond?
Opportunities for involvement
• Students
• Physics Faculty
• Education Researchers
THE LAB TRANSFORMATIONLearning goals, renovations, course redesign, curriculum redesign, assessment
Particular opportunities of a lab
Ready for active engagement Significant investment
Lots of space
Expert experimentalists
Small class sizes
How can we take advantage?
Goal #1: Course transformationExcellent for students• Develop experimental expertise• Modernize• MotivatingExcellent for faculty • Easier to teach• Easier to manage and maintainBroader impacts• A target for our lab sequence• A model for other schools
No lab manager
NSF funded. Share it!
Goal #2: A PER Research Project
Expanding research in PER• Minimal PER in labs• What should a lab for the 21st century look like?• What are students really learning?
Research-based resources• Example course materials• Assessments• A framework for redesigning labs
Spring 2011 classroom observations
1.Clear goals needed.
2.Applications needed.
3.Data analysis help.
4.Lab reports heavily emphasized.
5.It’s the best lab course.
Science Education Initiative Transformation Model
What should students
learn?
What are students learning?
What approaches improve student learning?
Consensus learning goals Assessments
Research-based curriculum development
DepartmentFaculty
PER Postdocs
Development of Learning Goals22 faculty Literature Community
LEARNING GOALS
Modeling Design
Technical lab skillsCommunication
Model: • Simplified• Predictive• Limited
applicability
Modeling• Developing• Testing• Refining
Four broad themes emerged
1. Modeling
2. Design
3. Communication
4. Technical skills
Development of Learning Goals
LEARNING GOALS
Modeling Design
Technical lab skillsCommunication
Math-physics-data connection
Statistical error analysis
Systematic error analysis
Modeling the measurement
Experimental design
Engineering design
Troubleshooting
Basic test and measurement equipment
Computer-aided data analysis
LabVIEWArgumentation
Integration into the physics discourse community
Development of Learning Goals
LEARNING GOALS
Modeling Design
Technical lab skillsCommunication
Math-physics-data connection
Statistical error analysis
Systematic error analysis
Modeling the measurement
Experimental design
Engineering design
Troubleshooting
Basic test and measurement equipment
Computer-aided data analysis
LabVIEWArgumentation
Integration into the physics discourse community
Systematic error analysis
Students should be able to test and develop models for sources of systematic error in their measurement devices and systems under study.
Why?1. Understanding systematic error is regarded by faculty as
an expert skill, yet it is largely absent from our lab courses.
2. Modeling provides a natural framework for discussing systematic error.
Systematic error analysis
Overhaul of the entire lab
Before: Abandoned darkroom. Always locked.After: Modern physics.
Physically integrating lecture and lab
Old: Unused space Lecture across the street. Topics tangential to lab work.
“lecture” space in same room as lab
New: Space for 16 students Activities in
Mathematica LabVIEW Data analysis
Student oral presentations
Modernization of the optics labs
New: 10 versatile optics workstations research grade equipment More open space.
Standard optics workstation
4 Redesigned Optics Labs
A New Suite of Lab Activities
RESEARCH AND ASSESSMENT Developing a framework of modeling in experiment Students’ expertise in modeling Assessing students’ attitudes about experiment Experimental skills development (computation, design, …)
Modeling (almost) a century ago“In 1930, I wondered how Newton’s laws of motion could give such a good description of phenomena studied in the undergraduate laboratory which was an integral part of Physics 1A. After some fruitless speculations, I decided that the most important object of physics was to study interesting laboratory phenomena, and to try to make a mathematical model in which the mathematical symbols imitated, in a way to be determined, the motions of the physical system. I regarded this as a game, to be taken seriously only if it worked well.”
-Willis Lamb 1955 Nobel Prize for the “Lamb Shift”
Modeling in the 1980’s“For the most part, the modeling theory should appear obvious to physicists, since it is supposed to provide an explicit formulation of things they know very well. That does not mean that the theory is trivial or unnecessary. Much of the knowledge it explicates is so basic and well known to physicists that they take it for granted and fail to realize that it should be taught to students.”
-David Hestenes
Theoretical physicists and innovator of the model-centered instructional strategy in physics a.k.a. “Modeling Instruction”
Modeling in high school and intro college
High School
Approx. 10% of HS physics courses
Intro college (examples)
Rutgers physics lab for non-majors
Intro calculus-based physics
RealTime Physics Labs (Wiley): Technology enhanced modeling
But will it work in the upper-division lab course?
If so, what would a “model-centered” curriculum look like?
Modeling is implicit in traditional labs
Key ingredients of the traditional lab:1) Interesting physical systems: complex, but model-able.
2) Quantitative comparison between theory and experiment.
The main problem: Students only play part of the “modeling game.”Where’s the building and refining of models?
Toward a framework of modeling in experiment
Hestenes, D. Toward a modeling theory of physics instruction. American Journal of Physics 55, 440 (1987).
Description Stage
Formulation Stage
Ramification Stage
Validation Stage
David Hestenes’ Modeling framework
Essentials of a traditional lab course
REAL WORLD STUFF
DATA AND THEORY COLLIDE
Measurement probes
Real-world physical system
interrogated
ComparisonIs the current data good enough?
How can I get better agreement?
Stop
YesNo
“Theory” = a model of the physical system
Two contributions to the model:
(1) fundamental principles
(2) Specific situation
Two limits on model validity
Real-world physical system
ComparisonIs the current data good enough?
Specific situationIdealizations?
Unknown parameters?
Physical system model
PrinciplesApproximations?
abstract
predictions
Define a measurement model, too.
PrinciplesApproximations?
Specific situationIdealizations?
Unknown parameters?
Measurement probes
Data
ComparisonIs the current data good enough?
Measurement model
Results with uncertainties
Full modeling framework
Specific situationIdealizations?
Unknown parameters?
PrinciplesApproximations?
Physical system model
abstract
predictions
PrinciplesApproximations?
Specific situationIdealizations?
Unknown parameters?
Data
Measurement model
Results with uncertainties
Real-world physical system
Measurement probes
ComparisonIs the current data good enough?
How can I get better agreement?
Stop
YesNo
Improve the measurement model
Improve the physical model
Tradition:
No model refinement
-OR-
One parameter left unspecified
Example: Pendulum for measuring g
Specific situationSimple pendulum
g is unknown
Newton’s laws
Physical system model
abstract
predictions
Oscillationperiod
Simple pendulumTiming gate
ComparisonIs the current data good enough?
How can I get better agreement?
Stop
YesNo
Improve the physical model
Fresnel Equations Lab
Plane waveMonochromatic
Linear polarized lightInfinite dielectric interfaceDetector close to interface
Maxwell’s equations and boundary
conditions
T(θ), R(θ)
Photodiode,Op-amp
Defining “zero angle”Calibrating the incident
powerFinite detector width.
T(θi), R(θi)
Physical system model
abstract
Laser beam,Rotation stage,
Lucite slab
(angle, voltage) pairs
Measurement model
Photodetector,voltmeter
ComparisonIs the current data good enough?
How can I get better agreement?
Stop
YesNo
Improve the measurement model
Improve the physical model
Gaussian beam?Polarization?Absorption?Scattering?Second reflection?
Implications of model-centered approach
1. Model both measurement and physical systems.
2. Systematic error is integrated into the experimental process.
3. Lecture courses provide the modeling tools for lab.
ASSESSMENT
Just a cheap knock-off survey?
VS.
The Original CLASS
It’s new!
How do our labs impact students?
“Traditional introductory laboratory courses generally do not capture the creativity of STEM disciplines. They often involve repeating classical experiments to reproduce known results, rather than engaging students in experiments with the possibility of true discovery. Students may infer from such courses that STEM fields involve repeating what is known to have worked in the past rather than exploring the unknown.”
-” PCAST Report,, Engage To Excel: Producing One Million Additional College Graduates With Degrees In STEM (2012)
Use learning goals for question topics
+ enjoyment, teamwork, confidence
E-CLASS DesignPairs of question
Postonly
Pre &Post
Actionable evidence for instructor
Gray, Kara, et al. Students know what physicists believe, but they don’t agree: A study using the CLASS survey. PRST--PER 020106 (2008)
Example: (modeling the measurement system)
Pre- and Post-semester
Post-semester only
Validation19 interviews. Students take survey and then explain how they answered it.
Ambiguity: “What do I think vs. what should I think?”
Add: “What would a physicist say?” (about lab class or their research lab?)
Modify: “What would a physicist say about their research?” (what about theoreticians?)
Modify: “What would do experimental physicists say about their research?” (final)
Initial implementationPost-test results from Spring 2012 in early May• 1140 (Intro) Experimental Physics 1
• 2150 Experimental Modern Physics
• 3330 Electronics for the Physical Sciences
• 3340/4430 Advanced Lab (Optics and Modern Physics)
Questions we can answer in December.Do we see any pre/post shifts in E-CLASS scores?Do transformed intro labs at other institutions impact E-CLASS scores?
Questions we can answer in May…Do students’ perceive course goals same as the instructors?Is there a progression toward expert-like attitudes, beliefs, and practices?
Conclusions & Open Questions
• Lab transformation is intellectually engaging, fun, and important.
• Students, faculty, and PER researchers all have something to offer.
There is a lot of work left to be done!
FOR MORE INFO
Personal website:http://spot.colorado.edu/~bezw0974/
Advanced Lab website:http://www.colorado.edu/physics/phys3340/phys3340_sp12/index.html
BONUS (DELETED) SLIDES
Comparison between pre-transformed PHYS 3340 and other institutionsTypical1) Mostly seniors. 2) 25-30 students per semester3) Optics and modern physics content
• Labs not connected to lecture course content4) Assessment based mostly on the lab reports.5) Fairly cookbook.6) Emphasis on statistical error analysis7) Expected 10-15 hours per week8) Students work in pairs..
Not typical9) The instructors rotate often (like the lecture courses)10) 10 weeks of guided labs, 5 week final project11) 2 “lecture” hours per week.
STM of gold diffraction grating
Full modeling frameworkReal-world
physical system
Specific situationIdealizations?
Unknown parameters?
Physical Model of System
PrinciplesApproximations?
abstract
predictions
Measurement probes
Data
Measurement model
Results with uncertainties
ComparisonIs the current data good enough?
YesNo