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15. The Research Base

  1. The Role of Research
  2. The Nature of the Research Literature
  3. Research Findings By Chapter and Section
    1. The Nature of Science
    2. The Nature of Mathematics
    3. The Nature of Technology
    4. The Physical Setting
    5. The Living Environment
    6. The Human Organism
    7. Human Society
    8. The Designed World
    9. The Mathematical World
    10. Historical Perspectives
    11. Common Themes
    12. Habits of Mind
  4. References

The references that follow are organized to match chapters and sections of Benchmarks, which in turn mostly match those of Science for All Americans. The list is very selective and includes only those references that met two criteria. One was relevance—some excellent papers were not included because they did not bear on one of the Benchmarks topics. The other criterion was quality—papers, however relevant, were bypassed if they were seen to have design flaws or their evidence or argument was weak. Even then, however, not all relevant and good papers are included. In many cases, a single paper has been used as representative of a number of similar reports.

It will immediately be clear that mathematics and the physical sciences have had the benefit of many more studies than have other fields. Perhaps that is because the subject matter lends itself to research more easily; in the next few years, though, perhaps the attention to cognitive research will increase in all fields.

Research Findings for Chapter 6: The Human Organism

Several studies have investigated the spontaneous development of student conceptions about The Human Organism. A general pattern that emerged from this research is that until the age of seven, students have little knowledge about the human organism. By age nine or ten, there is a marked increase in their knowledge (Carey, 1985).

No applicable research findings.


By the end of 5th grade, students know that babies result from the fusion of sperm and eggs. However, they often don't understand how the fusion brings new life. Before students have an early understanding of genetics, they may believe that the baby exists in the sperm but requires the egg for food and protection, or that the baby exists in the egg and requires the sperm as trigger to growth (Bernstein & Cowan, 1975; Goldman & Goldman, 1982).


Lower elementary-school children understand that death is irreversible and inevitable (Lazar & Torney-Purta, 1991). They usually think death is caused by an external agent but do not connect death with what happens within the body as a result of these external events (Carey, 1985). Around 3rd or 4th grade, students understand that death means the cessation of bodily functions (Carey, 1985).

Internal organs

Lower elementary-school students may have little knowledge about internal bodily organs and think the contents of the body are what they have seen being put into or coming out of it (e.g., food, blood). Upper elementary students can list a large number of organs (Gellert, 1962); however, a sizeable proportion of adults has little knowledge of internal organs or their location (for example, few adults can draw the stomach and the liver in reasonable positions) (Blum, 1977).

Nervous system

By the end of 2nd grade, students know that thought is needed for different kinds of activities (e.g., motor acts) and as a result, know the brain is required for these activities (Carey, 1985). Fourth-graders know the brain helps the body parts but do not always realize that the body also helps the brain (Johnson & Wellman, 1982). Whether upper elementary-school students can achieve this under-standing with adequate instruction needs further investigation. Upper elementary-school students attribute to nerves the functions of conducting messages, controlling activity, and stabilizing the body (Gellert, 1962), but even after traditional instruction about the brain and the nervous system, 5th-grade students appear not to understand yet the role of the brain in controlling involuntary behavior (Johnson & Wellman, 1982).

Circulatory system

Lower elementary-school students know about circulation and something of the blood's relation to breathing. Upper elementary-school students realize that the heart is a pump, but they are not aware that the blood returns to the heart (Carey, 1985). Students of all ages hold wrong ideas about the structure and function of blood, the structure and function of the heart, the circulatory pattern, the circulatory/respiratory relationships, and the closed system of circulation. Misconceptions concerning the circulatory pattern, the circulatory/respiratory relationships, and the closed system of circulation are difficult to change (Arnaudin & Mintzes 1985, 1986).

Digestive system

Lower elementary-school students know food is related to growing and being strong and healthy, but they are not aware of the physiological mechanisms. By 5th grade, students know that food undergoes a process of transformation in the body (Contento, 1981; Wellman & Johnson, 1982).

Respiratory system

Lower elementary-school students may not know what happens to air after it is inhaled. Upper elementary-school students associate the lungs' activities with breathing and may understand something about the exchange of gases in the lungs and that the air goes to all parts of the body (Carey, 1985).

In recent years, research on student views of the nature of the learning process has received increased attention. Several techniques for improving student knowledge of the learning process have been devised. Examples include encouraging students to construct concept maps (Novak & Gowin, 1984), to think about what they have learned and how they have learned it, and to document their learning in diaries. Students' ideas about learning appear to resist change (Baird & Mitchell, 1986), but long-term interventions can improve their knowledge of the learning process and their learning behavior (Baird, Fensham, Gunstone & White, 1989).


Elementary-school students may have the following ideas about germs: Germs are microorganisms causing illness; germs enter the body through the mouth while eating and leave the body through the mouth; every illness is caused by germs; all diseases are caused by the same kind of germ; the process of infection is automatic; any infection in the body necessarily makes it ill; and when medicine is administered, healing takes place immediately (Nagy, 1953). (This admittedly dated study is still cited by many authors.)

Causes of illness

Lower elementary-school children may think that illness is the result of misbehavior and realize that they are ill only when they are told that they are by others or when their illness has a behavioral impact, such as having to stay in bed or to go to the doctor. Upper elementary-school children may believe that all illnesses are caused by germs and are contagious. As students grow older, their beliefs about causes of illness begin to include also the malfunctioning of internal organs and systems, poor health habits, and genetics. Upper elementary students can understand that a change in internal body state or the experience of symptoms is the consequence of illness (Hergenrather & Rabinowitz, 1991).


Students of all ages focus on the physical dimensions of health and pay less attention to the mental and social dimensions. Students associate health primarily with food and fitness (Brumby et al., 1985; Moon et al., 1985). Middle-school and high-school students' wrong ideas about the causes of health and illness may derive from cultural knowledge (Rice, 1991; Prout, 1985).

Students of all ages tend to believe that many factors they consider important to their health and life span are also beyond their personal control (Brumby et al., 1985; Merkle & Treagust, 1987). After instruction, middle-school students appear to have accurate knowledge about nutrition and physical fitness, but they are often unable to explain their knowledge in scientific terms (Merkle & Treagust, 1987).


Lower elementary-school children know that there are different foods, that there are good foods and bad foods, and that there are different nutritional outcomes such as variations in size and health. In addition, they are aware of certain limits (drinking just water leads to death; eating only one thing—even one good food—is insufficient for good health). They still may believe, however, that food and water have equivalent nutritional consequences; height and weight are similarly influenced by amount of food eaten; and energy and strength result from exercise but not nutrition. These misconceptions tend to fade by the end of 5th grade (Wellman & Johnson, 1982).

No applicable research findings.

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