Both problems can be addressed with newly available wireless technologies. Over the past year, we implemented one such product—-the Classroom Performance System (CPS) made by eInstruction—in our classes at the University of Texas at Austin (UT; Woods in biology and Chiu in physics). We informed students at the start of the semester that they would be required to buy a CPS wireless response pad, which resembles a simple television remote control (Exhibit 1), for $34 from the University Co-op. During most class periods, we posed questions in yes/no or multiple-choice format; students responded by using their pads. A set of receivers at the front of the classroom collected the responses and sent them to a computer, which rapidly analyzed and formatted the answers as histograms. Questions and responses were projected by a liquid crystal display (LCD) unit onto a large screen at the front of the room. The wireless system was less expensive, easier to install, and more robust than comparable hard-wired response systems.

Although more systematic study is needed, it appears that the technology significantly improved student participation and interactivity in the physical classroom. We often lecture with question/answer pauses, and the wireless system helped us use these pauses effectively—by breaking up the monotony of a straight lecture and emphasizing important points. For us, the technology clearly indicated which topics were easy or hard, which topics were controversial, and in general how well the students understood the material.

Question Types and Possible Uses

Response pads have labeled buttons that constrain the instructor to a yes/no or multiple-choice question format. Although this design may seem like a significant limitation, the medium nonetheless is effective with a number of question types. We have used the following three categories of questions.

1. Fact or process questions assess basic understanding of a topic. "How long ago did the Earth form?" is a simple example, but these queries can be made less straightforward. For example, Woods projected an animation of the HIV lifecycle on the screen; after letting the students watch the animation several times, he asked a number of relatively sophisticated multiple-choice questions: "Which of the following lifecycle descriptions is correct? Why do HIV particles put reverse transcriptase into the cells that they infect? Which part of the lifecycle do protease inhibitors disrupt?" Provided that the possible answers are worded with fine distinctions, such multiple-choice questions require students to think carefully before they respond.

2. Problem-solving questions require students to employ a chain of reasoning. Since the strength of the chain depends on its weakest link, we focus on individual links. The wireless questions that we pose in class tend to be short and typically involve only one or two links (Exhibit 2). As with fact or process questions, an effective way to assess student learning is to pose several answers that all appear reasonable.

3. Opinion or belief questions can provide interesting insights about prevailing attitudes in the class (Exhibit 3). Some questions are sensitive enough that students are likely to give honest answers only if they can respond anonymously. In our experience, this was initially problematic because the computer associates each answer with the specific student who provided it (based on a unique identifying signal put out by each pad). We bypassed this problem by having students trade pads with one another.

Other kinds of questions may be more appropriate for other subjects or different teaching styles. In this respect, the tool is considerably flexible—the only constraint is that the questions be posed in yes/no or multiple-choice format.

Benefits for Students and Instructors

The first and most valuable benefit for students is an increase in interactivity and class participation. In traditional large classrooms where the predominant instructional mode is lecture, students often feel that the class is impersonal because their input is infrequently or never required. The wireless system encourages all students to participate in every topic, regardless of how shy they may be. This feature is especially powerful when coupled with other interactive teaching techniques, such as having students discuss questions with their peers before answering. Second, students know where they stand with respect to other students. After the responses are recorded, the computer displays a histogram of answers. The instructor can then indicate which answer is correct; alternatively, the students can discuss or argue until they arrive at the correct answer. If most of the class answers a question correctly, the students who answered incorrectly may be motivated to read or think more deeply about the subject matter. Third, students can practice solving test-style questions. A common complaint is that test questions are not representative of the material covered in class, or that such questions surprise students in some other way. Daily use of CPS questions gives students repeated exposure to the kinds of questions that the instructor writes and emphasizes the concepts and ideas that the instructor thinks most important.

Our students enjoyed the CPS tool and thought that it helped them learn the material presented in class (Exhibit 4). When Woods announced the technology to his class, a student near the front shouted out, "It'll be just like Who Wants to Be a Millionaire!" That sense of enthusiasm persisted throughout the semester. Many students seemed amused that their answers would be registered and therefore matter.

The tool is also eye-opening for instructors. In the classroom, most teachers verbally inquire whether everyone understands the material being presented. A nod from a single student may prompt the instructor to prematurely say, "Great. Let's move on." Wireless response systems eliminate this problem. By asking response questions throughout the class period, instructors can stay in touch with the level of student understanding. Often, topics that we believed to be difficult were in fact easy for the students, and vice versa. The net effect was that we could fine-tune our teaching effort to the pace of student comprehension.

In our classes, use of the CPS response pads appeared to increase attendance rates (see Exhibit 4). This effect probably stemmed from two factors. First, if students felt that their input contributed to the operation of the class, they may have been more likely to attend. Second, some fraction of the total points available to students depended on day-to-day participation. As mentioned above, each pad sends a unique identifying signal that is associated with a particular student, and the computer keeps track of each participant's responses. We had the CPS software generate a log file after each class session, and we used these files when assigning grades. Typically, we made 5–10% of the course points available through wireless participation. These points usually were not dependent on answering correctly, just on participating. This policy encouraged participation without turning every lecture into an examination. Instructors can, however, use the CPS as a testing tool if they wish.

Pricing and Distribution

At the University of Texas, we used what is called a "bookstore model." The University Co-op bought response pads from eInstruction and then resold them to students. Initially, the Co-op agreed to sell the pads for $34 each and to buy them back at the end of the semester for about one third of that amount. Although we felt that this cost was reasonable, it was still an extra expense that the students had to shoulder. The burden has eased this fall, with the dropping of the student purchase price to $17.50. Including sell-back at the end of the semester, the student's net cost for the response pad is now about $15. Whatever the charge, student reactions will depend strongly on how well the instructor integrates the technology with the course material.

Each of our classrooms was equipped with one or more receivers and, in some cases, a hub to coordinate signals from multiple receivers. A system with two receivers and a hub can service a class of approximately 250 students for roughly $1,000. In our college, the dean recently equipped seven classrooms for a total hardware cost of $7,000. Other forms of response technology can incur significantly greater expenses. Equipping large classrooms with hard-wired response technology, for example, can cost more than $20,000 per room. Thus, the wireless system represented a substantial savings. Of course, several other items are necessary: A computer must be available to run the (free) software and collect student responses, and an LCD projector is needed to display the results. To minimize additional expenses, our college targeted technology classrooms that had been previously equipped with computers and projectors.

The CPS wireless response technology is an effective tool for engaging students, understanding how well they grasp material, and finding out what they think about current issues. It is relatively inexpensive, easy to use, and reliable, and it can be readily integrated into previously established class material. We intend to continue using the system in our classrooms and have convinced a number of our colleagues to adopt the technology as well.

[Editor's note: Art Woods and Charles Chiu are not affiliated with eInstruction and do not have any financial interest in the company. Additional information on how the CPS system is used on their campus is available at the UT-CPS Support Home Page.]