Georgia Department of Education
Ga Virtual Learning: Magnetism
In this interactive unit students will see how magnets work and how they are used in some of the most useful and common devices today.
Georgia State University
Georgia State University: Hyper Physics: Magnetic Domains
A great introduction to magnetic domains, including pictures which illustrate the effect on domains caused by external applied magnetic fields.
Other
University of Kiel: Paramagnetism
Although this is a technical description of paramagnetism, with many equations, it is still possible to glean conceptual information with a little bit of work.
Wolfram Research
Wolfram Science World: Magnetic Permeability
This site defines magnetic permeability in terms of magnetic fields, and relates magnetic permeability to magnetic susceptibility and relative permeability.
Wikimedia
Wikipedia: Paramagnetism
This Wikipedia site is an introduction to paramagnetism and paramagnetic materials.
Wikimedia
Wikipedia: Permeability
This site from the encyclopedia Wikipedia provides a concise definition of magnetic permeability given in terms of magnetic flux density and magnetic field strength.
Oswego City School District
Regents Exam Prep Center: Permeability
A good visual introduction to permeability, comparing the magnetic permeabilities of air and iron. This site provides a good conceptual introduction to this topic.
Tech Target
Whatis.com: Permeability
This resource defines magnetic permeability and then describes how it is used to classify materials as diamagnetic, paramagnetic, or ferromagnetic.