Preconceptions Summary
Student preconceptions (misconceptions, naïve understandings) are important for teachers to uncover, address, challenge and extend. These are commonly held (but not always scientifically accurate) ideas that children bring to the classroom. Students come to school with ideas about the world and science principles because of experiences and observations that have helped to shape those beliefs. Learners hang onto those ideas until multiple experiences cause them to question previously-held beliefs and to form new explanations.
Educators need to discover student preconceptions and be aware of the related scientifically accurate ideas. It is the teacher’s role to facilitate learning experiences that challenge inaccurate ideas, solidify developing ideas, and reinforce and extend scientifically accepted ideas. Knowing student preconceptions helps educators to ask probing questions and craft experiences to move students along to greater science understanding.
Below is a summary of the preconceptions and scientifically accurate ideas related to the Magnets and Motors unit:
Preconceptions about Poles of Magnets:
Magnets simply attract uniformly.
Some students don’t know why the compass always points in the same direction.
Scientifically Accepted Ideas:
Magnets have two poles at either end.
Compasses align themselves with magnetic fields.
Preconceptions about Materials Attracted to Magnets:
All metallic materials (aluminum, copper) are attracted to magnets.
All silver colored items are attracted to a magnet.
Scientifically Accepted Ideas:
Only specific materials have magnetic properties.
Preconceptions about How Magnets Work:
Magnetism is a chemical reaction.
Magnetism is a type of gravity that makes the magnet pull.
Electrons are in one magnet and protons are in another to make them attract.
Scientifically Accepted Ideas:
Magnetism is a property of atoms.
Preconceptions about Size and Shape of Magnets:
Magnets have only one shape - the bar shape.
Different types of magnets exhibit different types of forces.
The size of a magnet determines its strength.
Scientifically Accepted Ideas:
Magnets can have many shapes.
All magnets exhibit the same basic force.
The properties of atoms determine the strength of a magnet.
Preconceptions about Magnetic Field:
Only magnets can produce magnetic fields.
A magnetic field is a two-dimensional pattern of line surrounding a magnet, not a three-dimensional field or force.
Magnetic field lines exist only outside the magnet.
While magnetism may be able to pass through paper, it cannot pass through wood, a notebook, a table, or other thicker materials.
Scientifically Accepted Ideas:
The magnetic field is a volume of space where the magnetic force diminishes with distance.
Preconceptions about Flow of Electricity:
Electric current flows positive to negative because the button on top of the battery indicates the direction of flow.
OR
Electric current flows positive to negative because positive is stronger than negative (i.e., negative numbers vs positive numbers)
Electric current flows from both positive and negative ends of the battery and meets in the light bulb, thus lighting it.
Scientifically Accepted Ideas:
Electric current flows negative to positive.
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