In the United States, 15 percent of children and adolescents are overweight.40 Alarmingly, the proportion of overweight children continues to grow. Over the past two decades, the proportion of overweight adolescents has tripled. Children have fewer weight-related health problems than adults do. However, overweight children are at high risk of becoming overweight adolescents and adults. Overweight adults are at risk for health problems including heart disease, diabetes, high blood pressure, stroke, and some forms of cancer. Approaches to this major health issue focus on several areas, including educating the public about basic nutrition principles and the value of physical activity. Maintaining a healthy body weight and lifestyle requires a long-term commitment and relies on individuals making the right choices about food intake and exercise.
The Science of Energy Balance: Calorie Intake and Physical Activity has several objectives. One is to introduce students to the key concept of energy balance and provide a context within which nutrition concepts learned at other times can be better understood. Through inquiry-based activities, students investigate energy intake and energy output as they develop their understanding of energy balance. A second objective is to allow students to develop the understanding that achieving energy balance is a long-term, rather than a short-term, goal. The lessons in this module help students sharpen their skills in observation, critical thinking, experimental design, and data analysis. They also make connections to other disciplines such as English, history, mathematics, and social science. A third objective is to convey to students the purpose of scientific research. Ongoing research affects how we understand the world around us and gives us the foundation for improving choices about our personal health and the health of our community. In this module, students experience how science provides evidence that can be used to understand and treat human disease. Because the mission of the National Institute of Diabetes and Digestive and Kidney Diseases includes helping the public understand the importance of calorie intake and physical activity to their health, education is an important activity for the Institute.
The lessons in this module encourage students to think about the relationships among knowledge, choice, behavior, and human health in this way:
Knowledge (what is known and not known) + Choice = Power
Power + Behavior = Enhanced Human Health
The final objective of this module is to encourage students to think in terms of these relationships now and as they grow older.
Middle school life science classes offer an ideal setting for integrating many areas of student interest. In this module, students participate in activities that integrate inquiry, science, human health, mathematics, and science-technology-society relationships. The real-life context of the module’s classroom lessons is engaging for students, and the knowledge gained can be applied immediately to students’ lives.
“The module focuses on and supports scientific inquiry. It encourages learners to think hypothetically, to extrapolate, and to hypothesize. The module challenges students to reflect on personal choices, thereby empowering them to make better decisions regarding their own energy balance. The module engages students in the use of technology to promote better understanding of concepts, and to explore and analyze data.” —Field-Test Teacher
“The best aspect was the ability to individualize most of the things we did. This was good because it got us more involved. Another aspect was the Web site, which was a nice change from the usual media used in the classroom. The third good thing was that the lessons related to our lives more than most science, which made it more interesting.” —Field-Test Student
The Science of Energy Balance: Calorie Intake and Physical Activity meets many of the criteria by which teachers and their programs are assessed.
In addition, the module provides a means for professional development. Teachers can engage in new and different teaching practices like those described in this module without completely overhauling their entire program. In Designing Professional Development for Teachers of Science and Mathematics, Susan Loucks-Horsley et al. write that replacement modules such as The Science of Energy Balance can “offer a window through which teachers can get a glimpse of what new teaching strategies look like in action.”27 By experiencing a short-term unit like this one, teachers can “change how they think about teaching and embrace new approaches that stimulate students to problem solve, reason, investigate, and construct their own meaning for the content.” The use of a supplemental unit like this module can encourage reflection and discussion and stimulate teachers to improve their practices by focusing on student learning through inquiry.
The following table correlates topics often included in the middle school life science curriculum with the major concepts presented in this module. This information is presented to help teachers make decisions about incorporating this material into the curriculum.
|Topics||Lesson 1||Lesson 2||Lesson 3||Lesson 4||Lesson 5|
|Chemical composition of matter|
|Individual variation and susceptibility|
|Human health and medicine|
|Risk assessment and management|
|Relationships among science, technology, and society|
|Energy changing from one form into another|
|Organisms sensing and responding to environmental stimuli|
Next: Implementing the Module