Biology Curriculum, Gifted

Concepts and Principles

Most biology curricula focus on the essential facts, concepts, and principles that make up the content or declarative knowledge of biology. Ineffective curricula present these concepts as a list of unrelated ideas in chapters that are barely connected. Highly effective curricula focus on the structure of knowledge and the rich interrelationships among the concepts and principles.

For example, a given life science textbook might expect a student to know and remember several specific facts about veins and arteries, such as (1) arteries are thicker than veins, (2) arteries are more elastic than veins, (3) arteries carry blood from the heart to the rest of the body, and (4) veins carry the blood back to the heart. Current research has consistently demonstrated that facts like those above, learned in isolation from a larger organizing framework, are quickly forgotten after a test, nor do students readily apply them to new problems and situations. A more effective approach would stress an understanding of veins and arteries as part of the circulation system where the function of the veins and arteries influences and constrains its structure. Knowing that the heart pumps blood in spurts, for instance, makes it easier to see why elasticity would help arteries accommodate the variable pressure of the blood and would also make it easier to function as a one-way valve to prevent the backflow of blood into the heart chambers. The framework of the circulatory system provides an organizing structure for remembering key principles, as well as the facts and concepts that support and instantiate them.

Deep learning in a subject certainly includes adding new declarative knowledge, but it also involves fundamental restructuring of that knowledge into flexible, adaptive knowledge structures that are efficient for problem solving and decision making. This is accomplished by organizing factual knowledge and key concepts around a small set of powerful core principles that can be viewed as conditional statements with predictive power, such as an If–Then statement. Using the vein and artery example above, “If arteries carry oxygen to vital organs, such as the brain, and if oxygen is critical to the functioning of the brain, then cutting off arterial blood flow to the head for very long will injure the brain.” A small set of such conditional statements implies both treatment priorities and [Page 100]techniques in first aid, for example. Also, a conceptual systems view would facilitate solving novel problems, such as designing artificial arteries.

The knowledge schemas provide an organizing structure that facilitates retrieval as well as acquisition of knowledge, and increases the efficiency with which high performers learn. At one time, the main content of biology was cataloging important facts about the plethora of life on Earth. With such an approach, it was easy to lose sight of the forest for the trees, literally. Today, with biological content knowledge expanding at an exponential rate, it makes good sense to organize a biology curriculum around the two pillars of modern life science: the molecular biology of the cell and biological evolution, with the DNA double-helix being the conceptual strand that joins them.

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