Just-in-Time Teaching (in a Large Lecture Setting) (Mats Selen, UIUC Department of Physics)

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Just-in-Time Teaching (in a Large Lecture
Setting) (Mats Selen, UIUC Department of
Physics)

• Q Is conceptual understanding as important as
  problem solving skills?
• A YES, of course !
• Q What can we do to help develop this skill??
• Modify lecture structure ACTs
• Pre-Flights before every lecture
• Implementation
• Results

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Setting the stage

• Physics 101 overview
• Algebra-based intro physics.
• About 400 pre-med students per semester
• Covers mechanics, heat thermo, waves sound
• Very fast paced, lots of work, 5 credit hours.
• Weekly structure
• Two 1-hour lectures
• Active learning
• One 2-hour discussion section
• includes weekly quiz
• One 3-hour laboratory section
• Hands-on discovery
• Web based homework
• Great systemanother talk

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• Why we should stress concepts

Physics 101 Midterm Exam 1, Spring 2000
On this exam, the conceptual problems were worth
about 30 of the total.
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Pre-Flights !!

• Students are asked to answer a set of conceptual
  questions (on the Web) prior to every lecture
  (and discussion, and lab).
• The main structure is
• Students read about material in text.
• Students answer pre-flight questions on material
  prior to lecture.
• Physics 101 PFs due at 6am, lecture starts at
  1pm.
• Graded on participation, not correctness.
• Instructor uses pre-flight responses to guide
  lecture preparation.
• Stress difficult material
• Pre-flights are reviewed during lecture, often
  presented again a ACTs, and often capped off
  with a demo.
• With careful preparation, the pre-flights can
  form the backbone of the lecture.

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What I typed in a simple text file
What the students see on the web
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Simple setup on our NT server Text ( pictures)
for PF 2 in here
Notice Lots of folks use our web-based
grade-book
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The instructors interface to thestudent
responses (also on web)
Statistics
Free response
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Lecture 2, Pre-Flights 12

• If the average velocity of a car during a trip
  along a straight road is positive, is it possible
  for the instantaneous velocity at some time
  during the trip to be negative?
• 1 - Yes
• 2 - No

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Lecture 6, Pre-Flight Questions 78

• Two identical boxes, each having a weight W, are
  tied to the ends of a string hung over a pulley
  (see picture). What is the tension T in the
  string? see text 4.10 1. T0 2. TW 3. T2W

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Students see their own answers

• Two identical boxes, each having a weight W, are
  tied to the ends of a string hung over a pulley
  (see picture). What is the tension T in the
  string? see text 4.10 1. T0 2. TW 3.
  T2W

The tension on the string would be the same if
you hung the two boxes on the same end. making it
equal to 2W.
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Lecture 20, Preflight 1

• Suppose you float a large ice-cube in a glass of
  water, and that after you place the ice in the
  glass the level of the water is at the very brim.
  When the ice melts, the level of the water in the
  glass will
• 1. Go up, causing the water to spill out of the
  glass.
• 2. Go down.
• 3. Stay the same.

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Nice ToolsWe can filter on responses based on
other questions !!
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Lecture 20, Preflight 2

• Which weighs more
• 1. A large bathtub filled to the brim with water.
  
• 2. A large bathtub filled to the brim with water
  with a battle-ship floating in it.
• 3. They will weigh the same.

Tub of water ship
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Lecture 12, Preflight 2 3

• What physical quantities are conserved in the
  above collision?
• 1. Only momentum is conserved 2. Only total
  mechanical energy is conserved 3. Both are
  conserved 4. Neither is conserved

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Sometimes we are surprised...
Answers to question 1
Students with answers to Preflight 2 wrong
Students with answers to Preflight 2 right
All Students
Explanation Question was actually quite
abstract since student could not visualize
where the energy went
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Students have fun with answers...

• Shown is a yummy doughnut. Where would you
  expect the center of mass of this breakfast of
  champions to be located? (Explain your reasoning
  Homer).

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Some students thoughts on doing 50 pre-flights
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Pre-FlightsAre they worth the work ?

• YES

• Wellwhat is the work?
• Question preparation.
• Carefully chosen questions can be the backbone of
  the lecture.
• Takes some time to get it right.
• Last minute on the fly lecture preparation.
• Con Takes me all morning on the day of lecture.
• Pro Takes me all morning on the day of lecture.
• Benefits
• Students seem to like it.
• They know I take the time to read their
  responses.
• They have a stake in the lectures.
• I love it !!!!
• The most fun I have had teaching.