Magnetism - ideas related to its development in K-8 students
Kindergarten ideas that are very appropriate:
The least kindergarten students might know is - magnets are magnetic, but how would they know it? Would they know it because they observed magnets stick to some metals? Or Would they know it because they observed that magnets seem to pull toward and then stick to some metals.
- Identify magnets and non magnets
- Know that magnets stick to metal
- Feel ... push, pull, and push and pull magnets with slow deliberate movements
- Begin to see recognize metal, nonmetal,
- Identify properties of objects
- Classification by two unique properties. (Concepts: Objects can be classified into groups by unique properties. Most objects can be classified as having or not having a specific property.)
- Attract or not attract
It would be interesting to interview young students to try to diagnose how much they know about how magnets interact with say the refrigerator. Would they describe, in a convincing manner, that a magnet pulls toward the refrigerator before it touches it or is stuck? To an adult this seems obvious and wouldn’t seem necessary to ask. It seems so simple to feel the pull before it is stuck. However, can young children recognize that part of the experience? Or do they center on the fact that the magnet is sticking? Piaget’s theory suggests that development is incremental and the ability to accommodate information is limited by the student’s present understanding of ways to operate on the information they are sensing at the time. Since these are kindergarten students they may be content to focus on one variable at a time. Considering this among other characteristics of students at this age it would seem likely that most kindergarten students focus on the magnet stuck to the refrigerator and not be interested or coaxed to decenter, transform, reverse, seriate, and increment. All which seem connected to this idea or task and may be beyond most kindergarten students discovering on their own or even with adult questioning.
Kindergarten children are experts at learning language. Particularly putting labels on concrete objects, actions, emotional feelings, smells, tastes, touches, sounds ... Things that can be experienced with their senses (concrete). The rectangular piece of metal or rubberized cube that sticks to the refrigerator = magnet (label). Touches, smooth, rough, pull, push, color, shape, ... All the properties that different concrete things have. However, they may be able to recognize properties when they are called to their attention. But they don’t recognize or define objects by the kinds of properties that an object has. They have learned to recognize objects the same way that you recognize the black silhouette of a coyote plywood cutout stuck in a person’s yard. They look at the whole object and compare its shape to their mental representations of shapes of objects previously constructed and stored as a mental representation to find a match. So to expect kindergarten students to match words (labels) to physical objects or something that they personally experience is very appropriate. It’s a matter of motivation, not development. Just think how soon a young child learns the label for a McDonalds and a Happy Meal.
To help students move beyond identification of objects and ideas by visual outlines and surface ideas they must create an understanding of properties or characteristics and that everything is really labeled, identified, and classified by its properties and characteristics by reasoning. That reasoning includes reasoning about properties and identifying properties that are necessary, sufficient, or unrelated to identify and classify. Reasoning with the use of deduction and induction to solve problems with minimal information or to make inferences with incomplete information.
Therefore, the majority of a kindergarten teacher's time and student’s time should be spent collecting observable information (properties or characteristics) putting labels to all the different properties, and organizing the different properties into categories (color, shape, size, position, texture, sounds, smells, tastes...) how properties and information can be classified and how to make predictions based on past observations (If there are clouds in the sky it might rain. If there are no clouds in the sky, it won’t rain).
Beyond Kindergarten to third or fourth grade - If this is not the case and students are able to feel and explain the magnetic force as a push and pull, without immediately turning their attention back to sticking magnets onto objects with iron, then they should be able to describe an operational definition for a magnetic as the area around a magnet that pushes and pulls when one magnet comes close to another or pulls when a magnet interacts with iron (, or nickel, or cobalt).
However, this understanding isn’t attained until years later. In addition to it the complexity of the four different kinds of interactions between magnets is added, then students have to be able to understand and generate all possible combinations between two different possibilities. Fourth grade at the earliest seems to be when most students can begin to appreciate such combinations when they are given several different experiences that will result in their experiencing all possible combinations through trial and error with concrete manipulation, provided a good discussion of results, a matrix or other visual as a bridge to proceduralize a way to systematically generate all possible examples.
Sixth grade ideas the seem very appropriate:
- Relative position and motion
- Matter, mass,force
- Magnetism and magnetic field
- Electricity and electrical fields and flow of electricity
- Energy source, receiver, transfer
- Model - inductive and deductive reasoning
Discussion for these ideas:
Inductive reasoning could be used to infer a magnetic field and its shape by using a compass or iron filings to systematically explore around a magnet. The distance and position of the compass and position of the iron filings would be changed (independent variables or manipulated variables) and other variables would be controlled. Varied and repeated to collect observational data of the needle on the compass or the position of the iron filings (dependent variables or responding variables) through the three dimensional space around various magnets to collect observable and repeatable evidence to create a visualization or a visual model of a magnetic field.
The 3-d magnetic field is one kind of depth that sixth graders would be able to understand and create models with which to think about magnetic fields. Again, if they were motivated. It would take a lot of thinking and drawings, to first create a 3-D visual model, and then to animate it to use to explain what happens when magnets approach one another with different orientations. They would need to viusalize three dimensionally and conserve volumen and space. For students to attain science literacy this kind of depth of understanding is what must be achieved.
Deductive reasoning could be used to infer a magnetic field in an elector magnet. When the circuit is open there is no magnetic field around the bolt. When the electric circuit is closed there is a magnetic field around the bolt that has the wire from the electric circuit wrapped around it. Therefore, the flow of electricity must be creating the magnetic field.
If the number of batteries in the closed circuit are increased when connected in series or the number of turns of wire around the bolt are increased the number of objects or the weight of the combined objects that can be moved by the magnetic field increases. Therefore, by increasing the amount of electrical energy flowing around the bolt the strength and probably the size of the magnetic field is increased.
Transfer of energy is proportional to the amount of energy in the source and the method of transfer.
Scientific inquiry - observations of objects within three dimensional space,
History of science - Michael Faraday 1830+ moved a magnet in a coil of wire and discovered that doing so produced a current of electricity in the wire.
The least a sixth grader might know.
What can they know if they are motivated to know it? The answer to that is anything that exists or can be represented or modeled in the real world or in the imaginary world by an analogy to something that exists in the real world. Think about that sentence until you can own it. Anything a teacher plans to do with fourth graders and up should provide enough information to not only do that, but should also include overwhelming observable evidence to convince them beyond a reasonable doubt that the representation or model is accurate and will help them make accurate inferences to understand and explain their world.
Dr. Robert Sweetland's Notes ©