- By Richard Anderson
“… in the winter of 1813 & ’14 , during my first
College vacations, I attended
a mathematical school kept in Boston by the Rev. Francis Xavier Brosius . .
. On entering his room, we were struck at the appearance of an ample Black Board
suspended on the wall, with lumps of chalk on a ledge below, and cloths hanging
at either side. I had never heard of such a thing before. There it was—forty-two
years ago—that I first saw what now I trust is considered indispensable
in every school—the Black Board—and there that I first witnessed
the process of analytical and inductive teaching.” [May 1855]
Presentation technology has long had an influence on how we teach. In the wonderful
quote above, the abolitionist Samuel J. May described his introduction to the
blackboard and its impact on teaching. The quote illustrates a couple of key
points: That technology has an important role in supporting classroom instruction,
and that technologies perceived as beneficial to instruction will become widely
adopted. The blackboard is a very powerful tool for instruction—it allows
information to be displayed in a persistent manner, and can give the audience
a consistent view of far more information than can be held in short-term memory.
The blackboard becomes a mediating artifact that maintains a shared view between
the instructor and students to provide context for lecture and discussion.
Stepping forward almost two centuries from Samuel May’s visit to Boston,
projected electronic slides are becoming an important presentation tool in the
classroom. There are some significant advantages to using electronic slides.
Slides allow advanced preparation of material, improving organization of the
presentation and giving a means of showing information-rich content such as
complex tables, formulas, programs, and diagrams. Slides afford instantaneous
display, avoiding the inaccuracy and the time of copying material onto an overhead
projector or whiteboard. Electronic slides offer the further advantage of not
having to print slides. Additional advantages of online materials include ease
of preparation, sharing, and modification.
However, these advantages come at a cost in the classroom. Both students and
instructors complain about the impact of using slides in lecture. One colleague
expressed this directly as, “PowerPoint sucks the life out of a class.”
The basic issue is that electronic slides tend to script a lecture and do not
provide mechanisms to adapt the presentation to the audience. An important part
of lecturing is adjusting material in response to audience reactions and developing
spontaneous examples and explanations to clarify and expand on topics. The weakness
of electronic projection of slides is the absence of a means to alter or augment
the displayed material to do this.
Breathing Life into
At the University of Washington, we developed Classroom Presenter specifically
to address this problem, and to provide flexibility while using slides. The
idea behind Classroom Presenter is simple: support writing on top of slides
by using the Tablet PC as the instructor device.
When lecturing using Classroom Presenter the instructor writes on top of images
of the slides. These images can either be projected directly from the Tablet
PC, or can be shown from a second machine that is networked to the first. An
advantage of the latter configuration is that the instructor can be untethered
from the projector, and lecture while holding the Tablet PC. The networked version
also lends itself to use in distance courses. The single machine version has
the advantage of being easier to set up. Figure 1 shows the instructor view,
and Figure 2 shows the view displayed on the data projector.
A key part of our system is the use of the Tablet PC as the instructor device.
Tablet PCs enable integration of ink with slides, allowing annotation with natural
handwriting. The high-quality ink of the Tablet PC completely changes the writing
experience from earlier pen computers based on different technologies. (Our
system is not unique in combining slides and digital ink using the Tablet PC;
an increasing number of other systems combine slides and digital ink using the
Tablet PC, including academic systems such as DyKnow, and commercial applications
such as PowerPoint and Journal.)
In developing the application, we paid attention to the display of ink on all
devices, so that remote displays’ ink flows in sync with the instructor’s,
communicating the direction and speed of writing. A substantial amount of effort
went into designing the system as a tablet application. This meant using controls
optimized for pen manipulation in a mobile environment. We also designed the
system with navigation facilities such as the film strip and direct navigation
to a whiteboard.
Classroom Presenter has been used in a wide range of Computer Science courses
at UW and other universities. Courses have included introductory programming,
data structures, software engineering, and computer architecture. Both instructors
and students have been very positive about the system. Typical instructor comments
include: “It didn’t take any adaptation. I just talked/ discussed
and when I needed an example, I wrote. As easy as using the board,” and
“Being able to diagram and spontaneously work examples instead of having
to use a pre-scripted PowerPoint slide deck—felt like teaching a real
Connecting with Student Devices
As one would expect, instructors have made varied use of the system. Some instructors
have made extensive use of ink on slides, while others have retained a slide-based
style with only occasional marking. In presentation, ink is used both to convey
information directly with text and diagrams, and to link speech to slides through
attentional markings. Figures 3 and 4 show examples of usage from actual classes.
In both of these examples the meaning of the writing was dependent on the spoken
context and is not conveyed in the static image. Digital ink has allowed instructors
to conduct many activities not supported by electronic slides alone, such as
a “collective brainstorming,” where answers that students speak
out are written down and “process simulation,” where ink is used
on top of a diagram to show a dynamic process.
It has been observed that ink
is often used when responding to student questions. This supports the view that
the value of ink is in supporting spontaneous acts by the instructor. One interesting
pattern of use of ink that has been observed across instructors is frequent
underlining and circling when talking about mathematical formulae or program
code, as in Figure 3. This is done to give a persistent tie between speech and
slide content. Another important use of ink is to repurpose slide content, such
as changing an example on a slide to make it cover a different situation.
Classroom Presenter is just the first step in using electronic materials in
the classroom. The current work on Classroom Presenter is to expand its interaction
with student devices. One natural direction is note-taking, where the ink and
slides are broadcast to note-taking applications such as Brown University’s
Remarkable Texts, Microsoft’s OneNote, or the Classroom Presenter so that
the student can take notes on top of the instructor’s ink and slides.
Another direction is to provide mechanisms for the instructor to direct student
activities. One example that Classroom Presenter supports is student contribution
of slides. In this case, students write on slides on personal devices and send
them back to the instructor. The instructor then chooses student submissions
to display for class discussion. This activity has a number of benefits. It
engages the students by giving them an activity to perform in class, instead
of just listening to the instructor. It allows the instructor the opportunity
to screen submissions before displaying them, to choose ones that illustrate
different approaches. And it supports “going to the whiteboard”
in a way that everyone can contribute.
[Editor’s note: The development of Classroom Presenter
began when the author was on sabbatical at Microsoft Research working with the
ConferenceXP Project (www.conferencexp. net). The work is now being conducted
at University of Washington, with collaborators at University of Virginia and
University of San Diego. The software is available for non-commercial use from