The Framework outlines the importance of developing an understanding of scientific explanations for students. The goal is for students to not only be able to understand and apply standard explanations, but also develop their own explanations by analyzing existing evidence related to a phenomenon. As such, it's essential that science teachers facilitate learning environments that support this kind of exploration and critical thinking.

The aim of science is to develop theories that explain different aspects of the world. For a theory to be accepted, it must have ample evidence and provide a more expansive explanation than any other existing theories. (NRC, Framework, 2012, p.52)

In scientific terms, 'explanation' is defined as a claim that explains the relationship between two or more variables. Often, this claim is developed in response to a query. In order to generate valid data for their explanation, scientists design investigations and research.

Engineering is a systematic practice for problem solving. It includes steps such as defining the problem, then generating, refining and evaluating solutions. This philosophy is outlined in the Framework.

Encouraging students to construct explanations of phenomena, which can be based on their observations or generated models, is a critical aspect of conceptual change. This approach allows them to recognize the implications of scientific concepts and gain a firsthand understanding through active engagement.

Engineering involves the development of a design rather than an explanation. This process is iterative and systematic and includes elements that are distinct from scientific activities, such as setting constraints and criteria for desired qualities in a solution, forming a plan, creating prototypes or models to assess feasibility and function, selecting features to optimize design criteria, and refining designs based on simulated performance. (NRC Framework, 2012, p. 68-69).