Blackboards, PowerPoint and Tablet PCs in the Classroom

1
Blackboards, PowerPoint and Tablet PCs in the
Classroom

• Lecturer, Department of Physics
• University of Toronto

Collaborators David Harrison, Ruxandra Serbanescu
2
Talk Outline

• PowerPoint versus Tablet / Blackboard
• How we process visual information
• The advantage of the large field of view of a
  blackboard
• When a Tablet PC is appropriate
• Case Studies Classes of 1000, 35, and 85
  students

3
Our experience in a 1700 seat auditorium

• We taught calculus-based physics to 900 students
  in one huge section
• Big central screen, two side screens
• Tried pure Powerpoint for one quarter
• Other 3 quarters we used Tablet PC on central
  screen for real time development
• Major results, images on side screens
• Student survey showed preference for Tablet PC
  method
• Medium Pen was more readable than Fine Pen

4
Teaching Physics in a 1700 Student Auditorium
5
This Talk is Canned

• Students make it clear that simply replacing the
  use of the blackboard by a PowerPoint
  presentation offers them the opportunity to sleep
  in the dark
• even awake, they miss a key element in the
  learning process observing a professor think in
  real time, as he or she develops material step by
  step.
• - quotes from U of T Academic Planning Document,
  Office of the Vice President and Provost,
  Stepping Up 2004 2010

6
PowerPoint
SUCKS!

• So why am I using it????!
• The information Im delivering is descriptive,
  result-based
• (as opposed to analytical or method-based)
• Audience is familiar with the context
• Youve seen this kind of stuff before!
• You want me to hurry up and tell you the end
  result!
• PowerPoint is not the best way to teach new, long
  argument-based material to an unfamiliar audience.

7
Our experience in a 100 seat classroom smaller
class

• We taught second year physics to 35 students
• 14 lectures Tablet PC presentation, using
  PowerPoint as well as real-time notes using
  digital ink
• 21 lectures Blackboard presentation, plus Tablet
  PC PowerPoint on the side-screen
• Student survey showed blackboard-focused method
  was preferred

8
How We Process Visual Information

• The visual field has three regions
• Foveal - central 2 degrees
• of our gaze
• Parafoveal - extends 5
• degrees out from centre
• Peripheral - region beyond parafovea
• Studies of eye movements show
• Our eyes remain still during fixations (0.2 0.3
  seconds)
• Our eyes move very quickly during unconscious
  saccades (30-50 milliseconds)

9
How We Process Visual Information

• When reading, 10-15 of saccades are regressions.
• Regressive saccades increase with complexity of
  the text.
• Sometimes readers jump back many lines.
• Very large regressive saccades involve spatial
  memory.
• If previous text is no longer in the visual
  field, reading becomes more difficult.

10
How We Process Visual Information

• The visual field has three regions
• Foveal - central 2 degrees of our gaze
• Parafoveal - extends 5 degrees out from centre
• Peripheral - region beyond parafovea
• Studies of eye movements show
• Our eyes remain still during fixations (0.2 0.3
  seconds)
• Our eyes move very quickly during unconscious
  saccades (30-50 milliseconds)

• When reading, 10-15 of saccades are regressions.
• Regressive saccades increase with complexity of
  the text.
• Sometimes readers jump back many lines.
• Very large regressive saccades involve spatial
  memory.
• If previous text is no longer in the visual
  field, reading becomes more difficult.

maybe I should have presented it this way?
11
Advantages of Blackboards

• Blackboards in traditional classrooms have
  multiple panels
• Field of view is much larger than a single
  screen
• Much more text is visible at once
• Larger regressive saccades are possible
• Multiple panels can be planned to display one
  argument
• Students can review the argument as a whole.

12
Comparing Visual Fields
All pictures drawn to the same angular scale
4 blackboard panels, each 2.2 x 1.1 m
Projection Screen in room
Sheet of Paper, held 32 cm away from eyes
Back of 100 seat classroom (9 m away)
17 x 23 degrees
Back of 200 seat classroom (15 m away)
Back of 1700 seat auditorium (about 60 m away)
7x5m screen
13
Visual Fields are Not the Whole Story
BUT

• Readability of writing depends mainly on
• Thickness of strokes
• Distance of reader from board
• Readability also depends on
• Size of letters
• Lighting on board
• Cleanliness of board
• Distance of student from the board should not
  exceed about 10 m

14
Our experience in a 200 seat classroom medium
class

• We taught Physics for the Humanities to 85
  students
• Most lectures Tablet PC presentation, with
  occasional window-switches to images and
  animations
• 1 lecture Blackboard presentation
• Student survey showed strong preference for
  Tablet PC. Students said it was more readable.

15
Blackboard Visibility
Easily readable
readable
Difficult to read
16
View from the back of a 200 seat classroom, 15 m
away
Whiteboard or Blackboard
Tablet PC
17
Conclusions

• PowerPoint may not be the best way to present
  long arguments to a student audience.
• Blackboards offer
• Large field of view easier to read and process
  text
• Real time development of material
• Check readability of your presentation method
  from the back row!
• When blackboard is too distant to read, Tablet PC
  offers a readable alternative but field of view
  is sacrificed.