CD-ROMs and Hypermedia

CD-ROMs (Compact Disc Read Only Memory) were introduced as a new form of data storage for microcomputers. In the mid-1990s, CD-ROM drives became standard equipment on most new computers. Between 1988 and 1995 the number of public schools using CD-ROMs had increased 250% (Plotnick, 1996). During the 1997-98 school year, 97% of U.S. public schools reported using CD-ROMs (Market Data Research (MDR), 1999.) With a data capacity of 650 megabytes (MB) (the equivalent of approximately 450 diskettes), the popularity of CD-ROMs rose along with the increased use of multimedia and hypermedia. Software with elements of text, hyperlinks, graphics, photographs, sound, animation, and video can be packaged together on a single CD-ROM. The software generally allows nonsequential or nonlinear access to the elements providing for flexibility and interactivity (Levin & Matthews, 1997.)

CD-ROM software packages with multimedia elements inspired educators to study their teaching and learning potential. These elements are also present in many Web pages for education. Multimedia and hypermedia software share characteristics with incidental learning and discovery learning. There is unplanned learning that can take place and opportunities can be provided for learners to explore alternatives and study relationships (Heller, 1990). With its multimodal presentation, this type of software has been found effective for accommodating the needs of different learners in learning cognitive and procedural information (Ayersman, 1996). Science and mathematics are some of the content areas best suited to discovery learning and thus excellent test beds for the use of computers and technology. Rieber has worked extensively on the effects of animated representations on incidental learning [Rieber, 1991). He concludes that even though students extract incidental information from animated graphics without risk to intentional learning, they are dangerously prone to developing a scientific misconception.

Middle school students need to know at least the technology's representational aspect. The ability to manipulate and control different representational parameters allows students to explore new possibilities and inquire within the science itself. With the help of computers, a constructivist-oriented learning environment can be created in the classroom.The computers give students plenty of opportunities to test their ideas [Goldberg, 1995]. Computers are not just part of the curriculum, but the whole curriculum is based on the use of computers. All classroom activities are not done on the computers, the computers are used when necessary. In Goldberg's project the students become more aware of their own learning by writing journal reflections and extensive learning commentaries. The computer also acts as a source of ideas that can challenge the students without the image of authority that teachers used to have in science classrooms. Now the students have the responsibility to use the technology tools for their own benefit, not as distracting elements.

Linear and nonlinear presentation techniques can both be utilized within multimedia software. Each of these techniques has advantages and disadvantages for middle school students. For instance, a primary choice of entertainment for children is cartoon animation. This could suggest that linear animation software or video will maintain the attention of the children and therefore be able to stimulate their interest in the sciences. Handal and his group found that there were significant differences between the students' ability to recall and comprehend complex subjects as presented by linear multimedia as opposed to those presented through printed text. Furthermore, linear animated material used as a didactic tool was easier for students to follow and manipulate in comparison to nonlinear software materials (Handal, 1999).

Hypermedia-assisted instruction has been found to include numerous advantages: easy tracking and searching of references, individual exploring of both academic and nonacademic material, and keeping many threads of inquiry alive at once, allowing discussion about findings. Less obvious are the disadvantages which also exist: disorientation, cognitive overload, flagging commitment, and unmotivated rambling (Heller, 1990).

TI-83 calculator with CBL unit and pH probe. Image provided by author Lisa L. Grable.

Calculator-based Laboratory

Calculator-based laboratory (CBL) is a system which includes a graphing calculator, an interface box, and probes. This system is used to measure and store data of many kinds and display the data as a time graph soon after the measurements are made. Graphing calculators have become more common in mathematics classrooms during the past decade while the CBL system is becoming more common in science classrooms (Cassity, 1997; Clayton, 1990). CBLs are low in cost compared to other electronic data collection systems and are portable. The main producers of CBL equipment in recent years are Texas Instruments, Casio, and Vernier Software. The literature on the use of CBL consists mainly of practitioner articles, explaining ideas for use of the system in the science classroom (Brueningsen & Bower, 1995; Reno & Speers, 1995). There is apparently a need for more research studies on the educating of middle school mathematics and science teachers in the use of CBLs.

Microcomputer-based Laboratory

Microcomputer-based laboratory (MBL) include the use of a microcomputer with an interface box and probes to collect data. Probes are designed to collect all sorts of experimental variables including temperature, pH, distance, force, light intensity, and dissolved oxygen, to name a few. This technology is available to classroom teachers since the mid-1980s when Robert Tinker, Ron Thornton and associates at TERC produced the "red box" interface for the Apple IIe (Thornton, 1985; Tinker, 1985). The MBL system can be used to collect a large number of data points over a period of time, store it, and see the results graphically in real time. MBL interface boxes, software and probes have been available from Vernier Software and Pasco Scientific in recent years.

MBLs gained wide acceptance in college and high school science classrooms after Heather Brasell's seminal study comparing traditional paper-and-pencil graphing methods with the instantaneous displays of the MBL. Students have a significant increase in retention of graph understanding when they see the graph instantaneously while the data is being collected (Brasell, 1987). MBLs have not been widely-used in middle school classrooms in North Carolina for science or mathematics. More research on the educating of middle school mathematics and science teachers to use MBL in the classroom and the learning of middle school students while using MBL would be helpful.