Textbooks
and Tests that Talk Back
Summary:
New software
allows professors to provide
instant feedback
to students. Guernsey highlights a
physics class
at North Carolina State University
that utilizes
online quizes.
Lisa Guernsey
Textbooks and Tests that Talk Back
New software allows professors to provide instant feedback to students
UP HERE on the second floor of Cox Hall at North Carolina State
University, the students
in Physics 208 are facing their first quiz of the semester.
The quiz isn't a typical problem scribbled on a chalkboard
or printed on paper. Nor are its
questions of the "plug and chug" variety, in which students
are expected to recall
formulas they've memorized and plug in the correct numbers.
Instead, the quiz exists on a World-Wide Web page, displayed
on 18 laptop computers.
The 48 students, working in groups of two and three, have been
asked to measure the
strength of two electric fields simulated on the computer screens.
To answer the two
questions, they must play with the simulation, clicking and dragging
a green dot that
represents a test charge. As they move the dot around, they can
see how strongly the test
charge is attracted to, or repelled by, the electric fields.
"The whole setup," one student will say after the class is over, "is pretty slick."
But right now-with 15 minutes left to finish the quiz-coming
up with an answer is
paramount. The students type their answers into boxes on the Web
page and hit the
"submit" button. Red X's appear if the answers are wrong.
As the room fills with the
chatter of students debating and making suggestions, the X's are
popping up everywhere.
The students shake their heads and try the problem again and again,
jotting calculations
in their notebooks.
COMPUTER-BASED TEACHING
The red X's may elicit frustration from those in the throes
of a quiz, but to many educators
such automatic feedback is a critical feature of computer-based
teaching. The programs
are designed to let students check their answers instantly on
quizzes or homework,
without waiting for professors or teaching assistants to grade
the work. Often, say
professors who use the programs, immediate feedback encourages
students to keep
working on problems that are giving them trouble.
This Friday morning, for example, the instructors in Physics
208-John S. Risley, a veteran
physics professor, and Scott Bonham, a postdoctoral researcheraren't
worried about the
students' needing repeated attempts to answer the question. The
instructors' objective is
to teach the students how to think about physics problems, not
how to plug and chug.
The two physicists have asked the members of each team to record,
on paper, how they
came up with an answer. It is those explanations, rather than
the red X's, that will count
toward the grades.
"I'm not so concerned that they don't know the answer
right away," Mr. Risley says later. "I
want the quiz to enable them to learn the material."
The quiz is part of WebAssign, a program designed largely by
N.C. State professors for
use in introductory math and science courses. In addition to automatic
feedback, the
software records every submission, providing professors with detailed
accounts of
students' performance (http://www.webassign.net).
WebAssign is now the primary vehicle for quizzes and homework
problems in about 60
physics, math, computer-science, and statistics classes at N.C.
State. More than 45 high
schools and universities around the United States are also giving
it a try, helping N.C.
State test the feasibility of selling the software commercially.
If the product takes off, professors here say, WebAssign would
be part of a revolution in
teaching introductory science courses. The software, they say,
can alert professors and
students alike to gaps in the students' comprehension, helping
to avert the low test scores
that tend to turn people away from science.
"WebAssign can make physics more attractive," Mr.
Risley says. "The vast majority of
people need to be encouraged to learn this stuff."
CHECKING THE ANSWERS AT ANY TIME
For students, WebAssign is like having a textbook or quiz sheet
that talks back. The
software offers many of the same homework problems that appear
in the textbooks, and
it checks the answers at any time, day or night.
In most classes here, multiple tries don't count against the
students, as long as they find
the right answer by the time the homework is due.
Tim Goetz, a sophomore in Physics 208, says the software's
instant feedback has
become a critical part of how he learns. "There's nothing
better," he says. "It gets to where
you expect it. You can resubmit and resubmit until you get it
right."
How a Quiz Provides Instant Feedback
For professors, the program functions like a gradebook that
fills itself in, analyzing how
individual students and entire classes are handling assignments.
Instructors use
passwords to tap into WebAssign's logs and call up charts showing
which students are
having trouble and which material needs to be better explained
in class.
Such computerized grading and feedback systems are becoming
an integral part of
on-line teaching, whether it occurs as part of traditional courses
or in those taught at a
distance. Automatic assessment programs now come with courseware
like Blackboard,
TopClass, or WebCT, and with distance-education systems like those
offered by Real
Education Inc. Computer-savvy professors and instructional designers
on campuses
around the country are developing similar software that is customized
for specific
courses.
GRADING ESSAYS
Software for essay grading has appeared on the horizon as wellattended
by some
controversy. A researcher at the University of Colorado at Boulder
is experimenting with
a computerized system that evaluates essays by comparing them
to ones it has read
before (The Chronicle, September 4, 1998). And the Educational
Testing Service has
announced that it will start using computers, in addition to humans,
to help grade essays
on the Graduate Management Admissions Test (The Chronicle, January
29).
Some people have reacted to the developments with trepidation,
and have wondered
whether such subjective evaluations should be trusted to computers.
Even the thought
that computers might grade multiple-choice or fill-in-theblank
quizzes leaves some
educators rattled. Are computer programs, they ask, replacing
professors?
Professors at N.C. State answer that question with a hearty
No. If used correctly, they
contend, computerized grading programs let professors spend less
time grading and
more time teaching. WebAssign, they add, is designed to be used
for homework and
quizzes, not for exams that carry significant weight in determining
students' grades.
ENTICING STUDENTS TO LEARN
Mr. Risley, the professor administering today's quiz, has used
WebAssign for nearly four
semesters. He views the software as a tool that entices students
to learn.
"Students see immediately how they are doing in the class,
so that helps them stay
motivated," he says. In large math and science courses where
quizzes are graded by
hand, students may not find out how well they've done until long
after a concept has been
taught. "If you just get quizzes back three to four weeks
later, you lose interest," Mr. Risley
says.
The problem presented by quizzes and homework assignments in
large science courses
has hounded physics professors here, as well as elsewhere, for
years. How, they ask,
can a professor effectively grade hundreds of assignments every
week, even with a team
of teaching assistants? Some instructors, Mr. Risley says, have
simply decided not to
collect homework, leaving students with little incentive to complete
it.
By contrast, professors at N.C. State who use WebAssign are
asking students to take
quizzes and do homework more often than before, because the software
takes care of
the grading for them. Professors can also encourage students to
talk to each other about
the problems without worrying that one student will simply give
other students the final
answer. That's because WebAssign displays questions differently
to each student:
Randomized numbers are inserted in math problems, so that no two
students, or teams of
students, are working on exactly the same one.
Professors also say students using WebAssign are more inclined
to seek help from
professors and teaching assistants throughout the semester, instead
of waiting until
crunch times. Larry Martin, a visiting professor of physics at
N.C. State and WebAssign's
lead developer, says that after professors here started using
the software, students
showed up at the university's tutorial center in a steady stream
throughout the semester.
"It used to be that two weeks before the exam, they'd have
200 people jammed in there
screaming, 'I need some help!' "
Mr. Martin designed the WebAssign prototype four years ago,
when he was teaching at
North Park University, in Chicago. A year later, at a meeting
for physics teachers, he met
an N.C. State graduate student in physics named Aaron Titus who
was creating a similar
program.
In 1997, Mr. Martin came to N.C. State to work with Mr. Titus
in developing the software
further. Mr. Titus, who is now an assistant professor of physics
at North Carolina A&T
State University, had already begun creating a program that used
a data base of
Webbased physics questions. He chose simple multiple-choice questions
culled from
textbooks whose publishers allowed him to experiment with their
material. He and Mr.
Martin sought questions using video and animation, too, and they
soon incorporated a
series of such items that were being designed by Wolfgang Christian,
a physics professor
at Davidson College.
Mr. Christian had been experimenting with Java, the computer
language that enables
mini-programs called applets to be run over the Web. He had created
animated
physics-instruction programs that he called "physlets."
So far, he has designed 25
physlets, which have earned him both a National Science Foundation
grant and, just last
month, an award from the journal Computers in Physics. One of
his physlets is the
electric-fields problem that Mr. Risley asked his Physics 208
students to solve.
INTEREST FROM PUBLISHERS
The combination of Mr. Martin's automatic-grading prototype,
Mr. Titus's data base, and Mr.
Christian's physlets resulted in WebAssign, which was used first
in N.C. State's
introductory physics courses in the fall of 1997. Since then,
more than half a dozen
textbook publishers-including Addison Wesley Longman and Prentice
Hall-have jumped
on board. They say they are more than willing to allow their textbook
questions to
become part of WebAssign's data base of homework and quiz problems,
as long as
students in courses using the data base are asked to buy the books,
too.
North Carolina State has designed the data base so that, for
each course, WebAssign
displays questions only from the books that professors have asked
their students to use.
Now North Carolina State is starting to market the software,
using advertising and
demonstrations at physics-and-technology meetings to get the word
out. Professors who
want to use a basic version of WebAssign are charged a $250 setup
fee and are asked
to pay N.C. State $5 per student per class per semester. The university
owns the
copyright to the program, and Mr. Martin and Mr. Titus receive
royalties from its sales.
John Risley, with physics students at North Carolina State:
"The vast majority of people
need to be encouraged to learn this stuff."
Physics professors at about half a dozen universities have
signed up so far. Evaluations
from students at several of the institutions have been favorable.
But WebAssign isn't perfect, say a few students here.
Willy Huang, a sophomore in Physics 208, says that even though
he likes WebAssign, he
sometimes gets nostalgic for old-fashioned homework, like black-and-white
questions at
the end of a textbook chapter. "When I have to open a book,
I feel like I'm learning a lot
more," he says. "Sometimes, when I'm using WebAssign,
I feel like I'm using it just to get to
the right answer, not to really learn it. "
In addition, those who aren't accustomed to computers or the
Web sometimes have
trouble with the software. "I think the majority of students
are intimidated to a degree,"
says Mr. Huang's classmate, Mr. Goetz. "It causes stress-not
that we don't overcome it."
Students at N.C. State, he adds, know that technology is going
to be a big part of their
classroom experience. "When you arrive here, it's `Welcome
to the electronic age' in a
hurry."
DEALING WITH A POWER OUTAGE
Technical glitches, too, can create problems with the electronic
teaching tools. In fact,
when professors arrived at work on this Friday morning, they found
notices taped to their
doors: The power would be off for the weekend to accommodate new
construction. For
the past few hours, Mr. Risley's colleagues have scrambled to
find a way to keep
WebAssign's servers running despite the scheduled outage.
Meanwhile, he and Mr. Bonham are collecting quiz papers and
leaning over laptops,
answering questions from a few still-perplexed students. Several
other test-takers have
managed to solve the quiz problems: A chart at the top of their
screens shows their
progress, and the red Xs have disappeared. Those students are
now flipping shut their
laptops, slinging backpacks over their shoulders, and heading
out the door.
When Mr. Risley returns to his office, he hears good news:
A generator has been found
and the power crisis averted. WebAssign will be available all
weekend, as usual, sending
instant feedback to the students whenever they decide to take
a shot at their homework,
at any hour of the day or night.
Links to on-line demonstrations of computerized homework are
on The Chronicle's Web
site at: http://chronicle:com