Purdue University - Oxidation and Reduction
Excellent tutorial covering the basic concepts of oxidation-reduction.
Chem1 Virtual Textbook - Some applications of entropy and free energy - Oxidation-reduction: the fall of the electronShort introduction to the ideas from chemical thermodynamics providing the underlying coherence to oxidation-reduction concepts.
Oxidation-Reduction and Electrochemistry Resources
22 questions
figures for classroom presentation