Excellent survey of the following topics: Amino Acid Classification, Acid-Base Properties, Functional Significance of R-Groups, Optical Properties, and The Peptide BondKimball's Biology Pages - Amino Acids
Virtual Textbook of Organic Chemistry - Proteins, Peptides & Amino Acids
Important facts about amino acid chemistry very well presented. Highly recommended.Purdue University - Amino Acids
Excellent comprehensive discussion of the amino acids. Perfectly calibrated for the MCAT. (No, you probably don't have to have all the structures memorized, but it is good to recognize the characteristics of an amino acid from a given structure.) Includes a great discussion on amino acid titration.The Medical Biochemistry Page - Introduction to Amino Acid Metabolism
Advanced topic. Good overview of biosynthesis and catabolism of amino acids. Good reading comprehension exercise for the MCAT.