They create, refine, and argue about MODELS What do scientists do? They create, refine, and argue about MODELS

In their most simple form, models can be stated as rules... As the runner increases speed, more blood will flow to her leg muscles.

These rules are really a set of relationships between objects, properties of objects and actions/events As the runner (object) increases speed (property)-- more blood (object) will flow (action) to her leg muscles (object).

Models are often stated in abstract terms in order to apply to a broader set of circumstances: As the runner increases speed, more blood will flow to her leg muscles. As exercise rate increases, more blood is diverted to working muscle groups.

Goal is to expand model to make it more inclusive, and to see if it is valid under all applicable circumstances (expand our model?) Does our simple rule state if there are upper or lower limits to this blood flow? (valid under all circumstances?) Will this model generalize to involuntary muscles in the body?

So…in evaluating computer simulations for use with students, ask yourself “What are the scientific model or models that underlie this simulation?” “Are these models accurate?” “What experiences will allow my students to understand this model on various levels of sophistication?”

Assignment : PART I 1. Select one simulation from today, identify one model and state it in generalized form (usually as a rule or set of connected rules). Use additional details if necessary to describe the model other than the rule/s. 2. Are there any factors that may influence the relationships in your model that you know about but cannot express it well in your model statement?

2. Because science always seeks models that are generalizable to different circumstances, state 2 circumstances in which this model would be helpful in predicting some natural phenomena. 3. Describe 1 circumstance where, because of unusual factors present, your model would not be sufficient to predict some natural phenomena. Give details about why it would not be predictive.

Assignment : PART II: Helping students with the simulation 4. To familiarize students with the objects, events, and relationships in this simulation (one of the three we used today), what simple, structured task could you ask students to do in the simulation? 5. After this initial structured task, what key ideas/concepts would you then introduce into a class discussion to help them further explore the model?

6. What advanced task might you eventually ask high level students to do with the simulation in order to challenge them? (quantifying models by taking data in the simulation is one possible way; there are others)