1. H-ITT PRS System in Phys 117A Shane Hutson, Assistant Professor, Physics and Astronomy
How do we use the PRS system?
Lecture lead-ins, i.e. Mazur’s ConcepTests
Interactive demonstrations
Problem solving exercises
Reading quizzes

2. ConcepTests – 2-3 per class
Goals -
get students to think about physics in class (not just take notes)
open discussion of common student misconceptions
lead-in to mini-lecture on relevant concepts
Mechanics –
Students have 2-3 minutes to submit answers
View graphical display of results
If 40-60% correct responses, use think-pair-share
Grading: Right=3 pts, Wrong=2 pts, No answer=0 pts

3. Example ConcepTest
A crate is moving to the right on a conveyor belt without slipping. The conveyor belt maintains a constant speed. The force of friction on the crate is
to the right
zero.
to the left.
After discussing w/ peers

4. Interactive Demos – In lieu of a ConcepTest
Goals -
Chosen to elicit common student misconceptions, not necessarily WHIZ-BANG
Get students to commit to their current model of the physical world
Demonstrate that they need a better physical model
Mechanics –
Pose question and setup demo while students take 2-3 minutes to submit answers
View graphical display of results
Run the demo and watch the surprise on their faces
Typically, % correct was close to random chance
Grading: Right=3 pts, Wrong=3 pts, No answer=0 pts

5. Example Interactive Demo
If the tension measured in Example #1 is 5 N,
what tension would the scale measure in Example #2?
A. 0 N (49%)
B. 2.5 N (10%)
C. 5 N (24%)
D. 10 N (16%)

6. Reading Quizzes – 5 min, 1 per week
Goals -
Get students to read material before class
Mechanics -
Students “scroll” through a series of 2-4 multiple choice questions
Does not show results to students after submission
Results are automatically graded and ed to instructor (Correct = 3 pts, Incorrect = 1 pt, No answer = 0 pts)
Typically 70-80% correct

7. Example Reading Quiz 1. The two general types of forces are
(20%) linear and centripetal.
(74%) contact and long-range.
(1%) normal and abnormal.
(0%) the light-side and the dark-side.
E. ( 4%) vector and scalar.
2. Newton’s 2nd Law states that the net force on an object determines that object’s
(81%) acceleration.
(4%) velocity.
(4%) displacement.
(6%) energy.
(6%) inertia.

8. Managing the H-ITT System
Initial setup is a little cumbersome
Automated registration for students (requires student’s to follow exact directions)
A web form would be preferable
Need roster in both classroom and office
But grading is straightforward
H-ITT Acquisition: Records classroom results and s them to you.
H-ITT Analysis: Save attachment on your cpu and assign points for various answers.

9. Managing the Students
Took about two weeks to get all the students registered
Important to run an interactive class (with modifications) even during those two weeks:
ConcepTests were not graded initially
Reading quizzes could be taken via PRS and/or paper
After first two weeks:
No more paper submissions
Everyone gets two freebies (forgot clicker etc)

10. Impressions
Benefits
Large majority of students do participate in class
Students more willing to ask questions,
e.g. “Why isn’t A correct?”
Difficulties
Students initially don’t trust the clicker to record correctly
Cannot cover as much material
Writing good ConcepTests is not easy
(physics, chemistry & biology resources at
Student inquiries about PRS grades can be time consuming
(to grade or not to grade?)

11. What do the students think?
What did you like most about the class?
“PRS”
“Interactive teaching – calling on students (knowing our names!) and use of clickers.”
“Loved the demonstrations and interactive environment of the class”
What did you dislike most about the class?
“Clickers should be strictly used for participation – not fair that you lose points if you get it wrong before it’s been taught.”
“The fact that I teach myself makes me mad”