The continuing expansion of scientific knowledge makes it impossible to teach all the ideas related to a given discipline in exhaustive detail during schooling years. The role of science education is not to teach "all the fact" but rather prepare students with sufficient core knowledge so that they can later acquire additional information on their own
To be considered core, the ideas should meet at least two of the following criteria and ideally all four:
Have broad importance across multiple sciences or engineering disciplines or be a key organizing concept of a single discipline;
Provide a key tool for understanding or investigating more complex ideas and solving problems;
Relate to the interests and life experiences of students or be connected to societal or personal concerns that require scientific or technological knowledge;
Be teachable and learnable over multiple grades at increasing levels of depth and sophistication
How do particles combine to form the variety of matter one observes?
How do substances combine or change (react) to make new substances?
What is energy?
How can one explain the structure, properties, and interactions of matter?
How can one explain and predict interactions between objects and within systems of objects?
How is energy transferred and conserved?
How are waves used to transfer energy and information?
"What is everything made of?" and "Why do things happen?" - These core ideas can be applied to explain and predict a wide variety of phenomena that occur in people's lives. And because such explanations and predictions rely on a basic understanding of matter and energy, students' abilities to conceive of the interactions of matter and energy are central to their science education. A fourth core idea introduces students to the ways in which advances in the physical sciences during the 20th century underlie all sophisticated technologies available today. This stresses the interplay of physical science and technology, as well as expands students' understanding of light and sound as mechanisms of both energy transfer and transfer of information between objects that are not in contact.