II Creative Reasoning Processes to Support Identifying a Pattern to be Explained

These are ways to help support student reasoning while they are engaged in identifying the pattern of interest.

There are two major categories on this page. A lesson usually pursues only one of these.

Exploratory Observations. These are observations conducted to identify a pattern to be explained. Exploratory observations are normally used at or near the beginning of a unit, in contrast with Evaluatory observations, which may be conducted later in a unit to test an existing model. Some ways to support students when making exploratory observations include:

Ask students to recall earlier observations
Ask students to make a prediction and test it
Ask students to collect observations
Use a demonstration and have the class make observations

Deepen an Explanation. The pattern to be explained by a model may exist within a phenomenon that is already partially understood by most students. In this kind of activity, teachers challenge students to they already have for a phenomenon by doing a round of modeling at a new level of detail.

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


Exploratory Observations

Exploratory observations are used to explore aspects of a phenomenon previously unknown or previously unattended to by students. For instance, students with little or no previous experience with electrical circuits may investigate circuits with batteries and bulbs, trying different arrangements in order to identify patterns that make a bulb light or that produce changes in bulb brightness. In ecology, students may design an investigation for a location near their school with few ideas about what they might find. In a unit on the human body, the teacher may lead students to recall their own experiences in order to raise questions about aspects of their own internal anatomy.

Example 1: Ask students to recall earlier observations

Teacher: You know that we can swallow through our mouth and breathe through our mouth or nose. How is the inside of our throat made so that we can do that?

Example 2: Ask students to make a prediction and test it

An example to begin a unit on energy in the human body at the elementary level could be to ask students to predict the direction of changes in breathing and heart rates when doing calisthenics. Then have them actually do calisthenics and measure their breathing and heart rate. Later this data could be recalled and used to motivate the development of models of the pulmonary and circulatory systems that explain why the rates increased.  

Example 3: Ask students to collect observations

In a high school electricity unit, the target model was that of a series circuit in which the “rate of charge flow” (current) was uniform throughout. Early in the unit, students were asked to observe the effects of adding a second mini light bulb in series with an existing single bulb. In addition to noticing that the brightness of each of the two bulbs was less than the brightness of the original single bulb, students also placed magnetic compasses under the wires of the circuit and observed that the magnitude of the needle deflection was less than when there was just one bulb. Students were often surprised to see that the needle deflection (and thus the current) was the same at various locations throughout the circuit since many made the assumption that current would be greater “before” the bulbs than “after” them.

This activity resulted in a discrepant event, where the outcome was not what many students expected. The activity was designed to address known student misconceptions about electrical current. Such observations of unexpected results can lead to very dynamic classroom discussions and innovative student reasoning as students dig for an explanation.

A circuit diagram shows three batteries with two identical bulbs connected in series.  A compass is shown taped below the wire leading from the batteries to one of the bulbs.Batteries and bulbs set up for each small group. A compass was taped into position and the students moved the circuit around over it. They placed some part of the wire over the compass, then closed the circuit and observed the deflection of the compass needle that resulted. This process was repeated to test different parts of the wire. The students were surprised to see that the magnitude of the deflection was the same at any point in the wire, whether “ before,” “after,” or between the bulbs. (CASTLE curriculum, Figure 1.2a)

Example 4: Ask students to collect observations

The teacher was going to teach diffusion but first, she asked the students to place an egg inside of vinegar to remove the shell and the egg was full of vinegar. By the next day they put the eggless shell on top of green corn syrup. The next day they observed that the was on top of the corn syrup deflated and they could observe the yolk through the membrane. The also observed that the corn syrup smell like vinegar. The teacher asked the students the following question: Can you come up with an explanation for why the vinegar came out????

Example 5: Use a demonstration and have the class make observations

The teacher opened a bottle of ammonia and had students raise their hands when they smelled it. The pattern of hands being raised from nearer the bottle to farther from the bottle was a pattern for them to explain.


Deepen an Explanation

The pattern to be explained may exist within a partially understood phenomenon. In this kind of activity, teachers challenge students to deepen an explanation or model they already have for a phenomenon by doing a round of modeling at a new level of detail. For example, a teacher may ask students to suggest a microscopic mechanism at work in a system they are already somewhat familiar with at the macroscopic level.

Example 6

T: What is it that causes gravity, anyway?

Many students have the general idea that “Everything pulls on everything else,” but don’t believe that the forces between, say, a ping pong ball and the Earth are equal and opposite. To arrive at this understanding, a unit in Preconceptions in Mechanics helps students move from the “Everything pulls on everything else” model to a more sophisticated model of “masslets” that can help them begin to reason about gravitational forces at a new level of detail.

A diagram of a large plastic air syringe is shown with the plunger partially depressed.Example 7

T: We have learned that pushing a plunger into an air syringe will cause an increase in pressure in the air inside it, and that the air ‘acts like a spring’ to push back on the plunger. But how does that happen? What causes the increase in pressure?

In this instance, students already have a macroscopic model of the phenomenon explained by the "spring-like air-pressure" model. Here the teacher takes that macroscopic idea as a pattern to be explained by asking students to explain what causes the pressure. Asking them to develop a microscopic model of pressure that involves collisions from gas molecules against the plunger is asking for a new and deeper level of explanation.


Supporting and Contributing Strategies

There are many Visualization strategies that may be helpful. Among them:

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

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:

Identifying multiple levels of discussion-based teaching strategies (Williams & Clement, 2015)