C&EN: COVER STORY - COMPUTER LEARNING HITS ITS STRIDE

As computation and modeling carve an ever-deeper niche in the field of chemistry, the chemists of tomorrow need to learn these tools and techniques today.

In addition to imparting to their students traditional wet laboratory skills, educators need to produce computer-savvy graduates who are ready to design molecules, model spectra, or analyze reams of data in silico.

"It's increasingly important for students to integrate fully the use of computers in learning, as well as doing, chemistry," said

Theresa Julia Zielinski, chemistry professor at Monmouth University, West Long Branch, N.J. At a symposium Zielinski chaired at the ACS meeting in Boston last month, sponsored by the Computers in Chemistry Division, speakers demonstrated that the computer-as-educational-tool is far more than a means for automating quizzes and homework.

Rather, computers can be sophisticated learning aids, helping students visualize complicated three-dimensional concepts such as potential energy surfaces or molecular docking. They can facilitate long-distance collaboration. They're also invaluable feedback tools, allowing educators to evaluate how well their students are learning.

Students today are also unprecedentedly computer savvy. "They're used to interacting on the computer now," said symposium speaker James B. Foresman, chemistry professor at York College of Pennsylvania. "It's more natural for them to do that than to start up an instrument or other piece of equipment," he said. When students enter a chemistry class, many of them can already do some calculations within programs like Netscape. "They can then gradually work into more advanced things," Foresman said.

And in fact, computer-based teaching techniques and tools have "dramatically improved--within the last year, even," thanks to factors such as increased computer power and more sophisticated software, Foresman said. What that can mean for students is to "be able to visualize at the molecular level or be able to take a spectrum obtained experimentally and see what each peak means in terms of the electrons in a molecule," Foresman said.

Both Foresman and Augustus W. Fountain III, director of the photonics research center at the U.S. Military Academy, West Point, gave symposium attendees an overview of educational computer programs used in chemistry classrooms.

West Point has a history of keeping on top of technology: Each student has been issued a computer since the 1980s, and classrooms have networked workstations and Web access.


ENLIGHTENED Students learn chemistry with the Web-based teaching system LUCID, which encourages understanding, rather than memorization. COURTESY OF DAVID HANSON/SUNY

A THOUSAND students take general chemistry every year, randomly assigned to an instructor. "That allows us to have an unbiased test bed for some technologies," Fountain said. And so he and his colleagues surveyed student performance in and response to a number of different computer-based learning systems.

"We continue to keep a finger on the pulse of what's going on," Fountain said. "As different types of technology come up, we try to get our foot in the door early and test it."

For example, the CPS (Classroom Performance System) is an online service that allows students to, among other things, take in-classroom quizzes anonymously. The researchers tested CPS in eight of 46 chemistry classes. The system allowed instructors to see how well students were understanding certain concepts, but there was "no dramatic improvement in student preparation or performance," Fountain said.

Another online system, WebCT, lets students submit homework electronically as well as take multiple-choice quizzes. Students get instant feedback on their performance, and instructors can see "how many people completed the homework, what answers students missed, and what they did well in. They can then discuss the information in class," he said.

The disadvantage of such systems, however, Fountain said, is that any interruption in the service, such as a downed server, prevents students from getting access to their work. Additionally, students can fall into the habit of guessing answers rather than doing the work.

Troy A. Wolfskill and David M. Hanson, chemistry professors at the State University of New York, Stony Brook, are trying to circumvent the pitfalls of guessing and pattern recognition that plague some learning systems. For the past five years, they've been developing a program called LUCID (Learning and Understanding through Computer-based Interactive Discovery), which, they say, helps students actually understand rather than just memorize concepts.

"Part of the trouble is that chemistry textbooks have so much information, the students are overwhelmed--they don't know what to do," Hanson said.

LUCID's questions, which require understanding to answer, help students focus on what's important, according to Wolfskill and Hanson. "For example, if they learned something by reading it in a textbook, we might ask them about the concept by asking them to draw a picture," Wolfskill said.

LUCID also uses a network, where students can get answers to questions and then evaluate them with their peers. "So essentially, they can get a sense of how people are agreeing or disagreeing on ideas," Wolfskill said.

THE IMMEDIATE feedback is a plus as well, they said. "Students hate to do problems and then wait a week to find out what the answer is supposed to be," Hanson said.

In the early days, however, when working with computer-based learning, instant feedback functions just gave the right answer. People soon learned, however, that students could plug in any old answer to get the right one.

So Wolfskill devised a strategy whereby the computer divulges only the student's correct responses. "If a student gets the wrong answer, the computer says 'you did this or that right, but you have the wrong answer,' " Hanson said.

"I want students to use a textbook," Wolfskill added. Providing them with a sense of what they've done correctly allows students to go to their text for suggestions to learn what needs to be done to get the right answer.

An unexpected plus turned up when students who used LUCID came back for follow-up interviews, Hanson and Wolfskill said. They found that the students who had later interviews spent time studying the material on their own, apparently motivated by curiosity generated through using the program. "That's really a fringe benefit I didn't expect," Hanson said.

Katherine I. Barnhard and John W. Moore, chemistry professors at the University of Wisconsin, Madison, are also trying to steer students toward problem solving. Barnhard described their interactive problem-analysis aid for online homework assignments: Rather than give students an answer to a problem, the program asks a series of questions designed to prompt the student to think about the problem.