Yvonne Ybarra is having an off day at the textile plant—no, make that an off week. Her job is to monitor the quality of the water used in the plant's production processes and to oversee the quality of water released into the nearby river (the effluent). She has to make regular reports to the Environmental Protection Agency (EPA) and other governmental agencies. But these agencies don't just take her word for it—they also monitor the quality of the river water.This week, Yvonne must submit a quarterly report to the EPA, as well as some reports to the plant manager. The last thing she needs is a complication, but that's just what she's got. The plant effluent is showing a higher concentration of residual dye than is acceptable. The effluent meets EPA standards, but it doesn't meet state standards or the plant's own standards....— From the "Water" unit of the ABC curriculum
As excerpt above shows, the Applications in Biology/Chemistry (ABC) curriculum offers students basic science concepts with a clear perspective on the role these concepts play in our everyday lives. The curriculum is designed for the middle 50 percent of the secondary student population, and for several of the major learning styles.
For those students who do not think and learn in a predominantly abstract way, teaching science concepts in context provides a concrete and familiar framework for new ideas. This helps them comprehend and retain the information and gives them a rationale for doing so.
Job profiles like the one above appear throughout the ABC units. They encourage students to focus on the world of work, and, in particular, on the many occupations in which scientific knowledge is needed. Each profile includes a brief description of the educational requirements and career path for that career, and typically includes scenarios that involve a specific occupational task or problem to be solved, and a related science concept. For example, by studying about a respiratory therapist's job, students learn how the body's nervious system controls blood-oxygen levels.
ABC's real-world applications present personal and societal contexts as well as workplace settings. Students may learn about nutritional requirements by exploring how these vary depending upon a person's dietary needs, age, and health. They may learn about pH in the context of a city's water-pollution controversy. Often teenagers are featured in scenarios (for example, adolescents' dietary concerns, skin care, and sexual development are treated). Scenarios that address societal issues are often based on actual events, such as the Exxon Valdez oil spill, Calgene's development of a blue rose, and the Montreal Protocol (a 1987 agreement among nations calling for industrialized countries to reduce their use of chemicals that threaten the ozone layer).
The Natural Order
This innovative science and biology curriculum was initiated and carried out by the nonprofit Center for Occupational Research and Development (CORD), based in Waco, Texas. The work was funded by a consortium of 46 states and three Canadian provinces and by the U.S. Department of Education's Eisenhower National Program for Mathematics and Science.
In writing the curriculum, the project team introduced the scientific principles with applications. Team members thus reversed the usual order of traditional science texts, where applications often appear as an aside or afterthought. The team also reversed the way in which most of us learned science.
The development of the curriculum was an arduous process, requiring extensive research. In writing about specific concepts, the design team, whenever possible, focused first on relevant applications, and only then on science content. The territory of applications was much farther from the familiar terrain of our academic backgrounds and thinking than we had assumed.
Even though the curriculum content is organized differently, the fundamental science information remains the same as it would be in a traditional text. ABC thus reflects our conviction that an applications curriculum can and should retain much of the content of traditional academic science courses. The instructional design is also consistent with the National Science Teachers Association'sCriteria for Excellence, and it follows the teaching recommendations of Project 2061: Science for All Americans.
Fundamentals of ABC
In addition to contextual learning and real-world applications, the ABC curriculum stresses cooperative learning. Students frequently work in small groups to share resources, provide mutual support, celebrate joint success, and generally achieve a common goal. These experiences simulate the teamwork that is essential in many of today's occupations.
Hands-on activities are also emphasized. Students simulate scientific problem solving in the laboratory, and visit job sites or libraries to conduct research. Lessons tend to require students to move around in their environment and manipulate materials to get information.
Each ABC unit contains 10 laboratory exercises and many additional hands-on activities that require less time and specialized equipment than do the labs. Most of the labs and activities are linked to an occupation. Some activities involve the creation of physical models of structures or processes that are otherwise difficult to grasp. Some help students make abstract ideas concrete (for example, making models of molecules or creating skits to demonstrate types of chemical reactions). Other activities involve simple demonstrations of scientific principles that students can perform independently at home using ordinary materials, or in the classroom with a minimum of equipment or setup.
These text-based activities typically take much less time than do the regular laboratory exercises in the ABC course. For example, in one natural resources activity that is designed for a single class session, students use soft drink cans, water, thermometers, and sunlight to demonstrate how temperature changes with the use of solar energy.
On-the-Job Applications
ABC's real-world applications are integrated into the science content of the curriculum. For example, in the unit "Water," the question of how to measure the concentration of solutions comes up. Through the vignette (shown in part at the beginning of this article), students are introduced to the relationship between the color of a solution and its concentration—in a friendly, nontechnical way.
Yvonne Ybarra's problem involves the concept of colorimetry, one of the most common methods of measuring concentration. Let's continue where we left off. Condition Red! Yvonne got the bad news from the computer in the plant control room, and she immediately called the plant's dye house."Paul, this is Yvonne. I think we've got a problem. I'm showing an elevated concentration of red dye in the effluent.""Now wait a minute, Yvonne, all my instruments show that everything's fine. Are you sure?""Well, I'm on my way to check it out right now. My printout shows that we exceeded plant standards about an hour ago. So it might be a good idea to start troubleshooting."Yvonne drove out to the plant's effluent-monitoring station by the river, checked the instrumentation, and confirmed that the control room readout was correct. Then she took her own sample of effluent, and even before it was analyzed she knew that the instruments weren't lying. There in the test tube was the evidence: water colored pale pink from the dyeing operations.
This scenario also sets the stage for the discussion of molar and normal concentration. In accompanying activities, students must calculate both molar and normal solutions.
In presenting applications, the units often require students to begin with the big picture and work quickly toward one or more details. The big picture usually involves the human dimension of an event—the teenager describing her weight problem, a farmer talking about crop yield, or the effects of the terrible Bhopal chemical accident. The text then progresses from the teenager's dilemma to a description of nitrogen fixation; from the horror of Bhopal to a discussion of the effects of density and molecular weight on gas dispersion. This macro-to-micro-level thinking assures students that the science principles are as much a part of the real world as anything they have observed.
The inclusion of hands-on activities in ABC was as high a priority as the inclusion of applications of science in context, and, as often as possible, we combined the two. For example, in one activity students are provided with a blank growth chart that can be used to track a child's growth rate. The teacher provides fictional information and asks students to plot the data on the growth chart and observe how they compare to normative values. This simulates one activity that a pediatric nurse might perform.
Real-World Labs
Just as specific examples help students make vital real-world connections when reading the text and engaging in the various activities, they also drive the laboratories. The labs, too, are primarily tied to occupational applications, but personal and social issues are sometimes featured as well.
Each lab is introduced by a scenario that involves a problem or a technique for collecting data. In some cases, these applications build on the ones presented in the text. For example, in the first subunit on microbiology, different groups of microorganisms are cast in various roles—disease causers, decomposers and recyclers, food and chemical producers, or some combination of these.
Early in the subunit a job profile introduces Peggy C., a bacteriologist who works in a clinical laboratory. As Peggy identifies pathogens, one of the routine procedures she performs is Gram staining, in which bacteria are stained with a solution of iodine and other chemicals. Later in the subunit, structural features of the various microbes are described. Students use plastic beverage bottles to build a model of a rod-shaped bacterium.
All of this sets the stage for another lab activity, "How Are Bacteria Identified?" The introduction to this lab includes a description of a bacteriologist's job in a candy factory laboratory. The bacteriologist, Robert C., uses Gram staining to identify microorganisms that cause food contamination and spoilage. In these ways, students learn what Gram staining is and how it is used in two distinctly different settings.
Explaining and Exploring
Writing reports, giving presentations, and debating are important aspects of many jobs today. Accordingly, many ABC activities call for students to exercise these communication skills.
Research activities are also a fundamental part of the curriculum. Library assignments sometimes specify databases and sources. The assignments are usually open-ended, requiring students to identify sources of information. In addition, many require students to conduct community-based research in which they call or write for information from local businesses or agencies, or interview people in various occupations.
The goal of these assignments is to help students gain skill and confidence in finding information, as well as to encourage them to actively consider the sources of information rather than being passive receivers.
We have found that for many research and communication activities, it's necessary to tell teachers and students how they're used in a given job. For example, activities that require students to make diagrams, flowcharts, or sketches are sometimes resisted by both teachers and students, who protest that they are not artists. Yet these skills are crucial to many jobs that are not strictly artistic.
Mix-and-Match Units
Because the ABC curriculum integrates academic and vocational material, it is being implemented in many ways. Practitioners have selected units to create courses on general biology, health sciences, agriculture, integrated science, and the environment. In addition, single units have been incorporated into existing courses.
Aware that the units can be configured in various ways, the design committee mandated that each one be capable of standing alone. This permits a useful teaching strategy—the teaching of a single science concept in different contexts. For example, the concept of pH is covered extensively in one unit, but is also discussed in seven other units.
Although evidence is still primarily anecdotal, recent exit exam scores have reinforced this evidence. Many teachers report that covering key concepts in different contexts helps their students better understand and master the concepts. It also should broaden students' abilities to make connections and use their knowledge, and, we hope, engender the joy of discovery. They'll put these abilities to use throughout their lives.
