Candidate components of metamodeling knowledge for a learning progression for modeling Nature of modelsModels can represent non-visible and non-accessible processes and features Different models can have different advantages Models are representations that have limitations in what they represent about phenomena Models can be changed to reflect growing understanding of the phenomena There are multiple types of models: diagrams, material models, simulations, etc.Purpose of models Models are sense-making tools for constructing knowledge Models are communication tools for conveying understanding or knowledge Models can be used to develop new understandings, by predicting new aspects of phenomena Models are used to illustrate, explain, and predict phenomenaCriteria for evaluating and revising models Models need to be based on evidence about the phenomena Models need to include only what is relevant to their purpose