In order to provide a starting point for a focused conversation, in what follows I am assuming that your child or pupil has been exposed at least to a Kindergarten-introduction to magnetism, along the lines given in the book What Every Kindergartner Needs to Know, Hirsch, E. D., Editor, referenced in our resources section.

In that same section, I have enclosed a few hot links to a few educational sites of interest, which you are welcome to explore at your own leisure as they possibly apply to teaching these concepts to young children; none of those sites is assumed as a background in what follows. Once again, the amount of information available is overwhelming and I personally believe in creating a crossroads to focus the attention of children. You are certainly more than welcome to experiment with other curricula, of course.

Magnetism Activities
One of the earliest activities you can carry out with your child or with your pupils is to study magnetism by means of a permanent magnet and a number of sample objects. These activities might involve classifying those materials that appear attracted by a permanent bar magnet as opposed to those that do not appear affected by it. Some interesting questions might be whether all materials are attracted by your magnet, whether magnetism goes through objects, and you may want to even build a floating compass.

Fundamental Interactions - Superforce - Unification
Magnetism is a manifestation of a fundamental interaction called the electromagnetic force. Fundamental interactions are ultimately involved in explaining everything we see around us in the universe and they include: gravitation, the weak force, electromagnetism (which we have just seen), and the strong force. All forces we experience in nature can ultimately be explained on the basis of one or more of these four. There has been a great effort to show that these four forces are actually manifestations of one ``superforce.''

This is a trend that started in the nineteenth century, when James Clerk Maxwell succeeded in showing that electricity and magnetism are manifestations of the same force, the electromagnetic force. More recently, scientists have shown that the electromagnetic force and the weak force are manifestations of the same interaction, referred to as the electro-weak interaction. This effort to explain all fundamental interactions as different manifestations of only one force is referred to as unification.

Refining conventional teaching about Neutral Objects
The interesting concept of dispersion forces, central to the research and development activities at InterStellar Technologies Corporation, challenges some of the facts children of all ages are usually exposed to in their education. For instance, when pupils cover electricity, they are told there are two types of charges, conventionally referred to as positive and negative. An object that contains any charge is referred to as charged ; if it contains neither type of charge, an object is referred to as neutral. Pupils are told that objects containing like charges (for instance both positive or both negative) will repel each other; objects containing opposing charges (positive and negative) will attract.

Then, pupils are told that neutral objects will exert no net electric force on one another. This is incorrect. In fact, neutral objects exert electromagnetic forces on one another. For instance, two neutral, spherical atoms, such as two helium atoms, will attract one another even though they are not going to react chemically and form a molecule, as two hydrogen atoms will, for instance. Similarly, a neutral, spherical atom in front of a perfectly neutral metal plate will be attracted by it, unlike what pupils are typically taught.

One of the most stunning manifestations of these interactions between electrically neutral objects was discovered theoretically by Casimir in the 1940s. He obtained a prediction that two metal plates, parallel to one another, would mutually attract even though they are perfectly neutral. This is referred to as the Casimir effect.

Of course, this concept presents an additional challenge for a pupil. One of the most challenging concepts for young children is that of accepting action at a distance between two objects that do not appear to touch one another. Magnetism, for instance, is completely invisible. What is ``touching'' the paper clip attracted by the bar magnet? The parent/teacher will usually explain that, in order for magnetism to work, there must be a magnet and a material sensitive to magnetism. For instance, a bar magnet will attract a paper clip, but not a piece of paper. Likewise, the paper clip will not be attracted by a piece of copper (at least not magnetically).

In the case of the Casimir effect, the challenge is to explain that there exists a force between the two neutral objects apparently only caused by their ``being there.'' Although this is certainly a challenging notion for anyone, including adult readers, perhaps it is important to expose the pupils to the fact that, although much of what happens around us can be explained on the basis of what we clearly see, sometimes we must focus on what we cannot see. The child is already learning that magnetism, electricity, and gravitation, cannot be seen in the common sense of the word. However, these forces are real, and they can be connected to some properties the child can be taught to expect by experience (magnetic materials, conductors, etc.).

The Casimir effect shows us that even objects that do not fit this characterization can exert a force on one another, and this force is, fundamentally, electromagnetic. What determines the exact behavior of this force is the shape of the objects, their surface roughness, their optical properties, and their temperature, among other things. This may be left as a challenge for the future, but the pupil should not move on simply believing that neutral objects ignore one another: that is wrong as the experiments show and the theory of electromagnetism explains.

Forces in Empty Space
One further point of great importance to the parent/educator is that one way to explain the Casimir force (one example of dispersion forces) is to not look at (for instance) the two parallel plates, but, instead, at the vacuum surrounding them. In other words, there is a way to explain what happens by concentrating not on the objects themselves, but on the vacuum around them. This is certainly a challenging notion. However, it is important to prepare the pupil to the fact that what happens in the universe may not only be determined by objects, but also by completely empty space. Once the child can stretch his or her mind to accepting the very existence of something like the vacuum, the mind is ready to deal with a number of interesting questions. For instance, what is left in space once everything else has been removed (with a pump, for instance) ? What did early scientists believe the vacuum is? Does the vacuum even exist?

By raising these issues as appropriate by age, one is taking a little extra step: from the fact that such a force as magnetism seems able to attract through an invisible force, we are now accepting the fact that forces may exist because somehow the nothingness of space is affected by objects in it. It seems exotic, but the child will study that these forces may be stronger than electromagnetism and gravity when two surfaces are very close.