II Creative Reasoning Processes to Support Model Generation

These are techniques to help support student reasoning while students are generating an initial model.

One or more of these can be used in any order.

Using Analogies to Support Model Generation
Supporting Model Generation by Asking Students to Provide Elements for an Initial Model
Providing a Partial Initial Model to Support Model Generation
Requesting Elaboration of a Partial Model and Gently Pressing for an Explanation

Something these processes have in common is that they do not attempt to yield a finished, scientifically accurate model on the first try, but to provide something that the teacher can help students build on during later modeling phases. They vary in what kinds of input are given by the teacher and lesson materials.

There are many Level I strategies that can help; a few are listed at the bottom of this page.


Using Analogies to Support Model Generation

Example 1

Teacher: Is there an analogy that you can think of that would explain why this thin filament light bulb would have a higher resistance than this thick filament? 

There are many analogies that could work. Students may suggest such ideas as straws or highways of different widths.

Example 2

When considering a new phenomenon, there may be close analogies to previous phenomena the class has studied. When a class began considering how oxygen might get into the big toe, the teacher asked, “Remember how food got from the network of blood vessels into the toe cells?”


Supporting Model Generation by Asking Students to Provide Elements for an Initial Model

Example 3

A wire is shown leading two and from a lightbulb, with the filament inside the lightbulb. Wavy lines extend away from the lightbulb, representing light leaving the bulb. Three small circles with negative signs inside them are shown approaching the bulb, their direction indicated by an arrow. The entire figure appears hand-drawn.When high school students prepared to measure current at different places in a circuit that contained two light bulbs, they expected to find more current “before” the bulbs than “after” them. To begin model construction, the teacher asked them to draw.

T: Can you draw what happens to the charge when it gets to the bulb?

In this way, the teacher focused the students on what was happening at one critical point in the circuit, the bulb, and asked students to provide their ideas by drawing them. The drawing represents negative charges approaching a bulb and light (but no charge) leaving it. Even though the drawing does not provide a complete representation of the phenomenon, several important model elements have been provided by the students and can be built upon.


Providing a Partial Model to Support Model Generation

Example 4

Black wavy lines extend along the top and bottom of the image, representing villi-lined intestinal walls. Green dots between the lines represent nutrients in the intestines.Teacher and middle school students were discussing where to locate capillaries with respect to the villi in the small intestine to increase nutrient absorption. The teacher asked, “Now to make this thing the most efficient machine...where do I want to place those capillaries? Put your heads together.” The students worked together in their group and then the teacher asked one student to draw the group ideas on an overhead that was in front of the class. The overhead already had black wavy lines representing the villi in the walls of the intestine and green dots representing nutrients; this was a partial model of the intestine provided by the teacher. The student ideas about capillaries were added in red.

This image is identical to the one above, but students have added hand-drawn lines in red to represent their models of how the capillaries would be arranged in the villi. Model A has three vertical lines inside the intestinal wall, near a villus. Model B has a wavy red line following the surface of villi, inside the intestine next to the nutrients. Model C has branching tree-like structures inside each villus.Although none of the student additions (A, B, or C) were scientifically correct, they resulted in three initial models that could then be evaluated and modified to arrive at the target model of the structure of the small intestine. The partial model provided by the teacher served to scaffold the students in their model generation.

(For what the teacher did next, see Level IV Model Competition: Example 3.)


Requesting Elaboration of a Partial Model and Gently Pressing for an Explanation

Example 5

In the electricity lesson described in Level II: Example 3 (above), the teacher asked the students to elaborate on their initial drawings.

T: So where does it (charge) go once it’s in the bulb?

S: It’s hot in there.

T: But once it’s there, where does it go?

Although the teacher did not evaluate the student contribution, he did press for an explanation because the student did not offer an explanation for where the charge goes.

Example 6

In a unit where students were generating initial models to explain how oxygen gets to the cells in the body, rather than evaluating the correctness or incorrectness of a student drawing, the teacher asked for more elaboration:

T: Does your drawing show where the oxygen goes?


Supporting and Contributing Strategies

Scientific drawings can be especially useful in helping students to generate an initial model. A teacher can start out with an outline of a model for students to fill in, as in Figure 1 above, or get students to draw their initial ideas on whiteboards. See:

I. Imagery Talk
I. Depictive Gestures
I. Scientific Drawings

Participation Strategies are especially important early in the lesson.

I. Participation Strategies


Articles, Papers and Websites

More in-depth discussion is found in the following paper by our team:

Generating, evaluating, and modifying scientific models using projected computer simulations (Price & Clement, 2014)

For other ideas on how to represent and summarize student ideas for models, see

Ambitious Science Teaching, a website from Mark Windschitl’s group at the University of Washington.