Mindy Slavis, a New York mother, had run out of ways to deal with her unruly teenager: She had been to parenting classes and tried a series of private and public schools. Her 17-year-old daughter, Alexandra, was cutting classes, smoking and taking drugs. When she stole her father's credit card and went on a spending spree, Mrs. Slavis decided she had to take drastic measures. She began looking on the Internet, searching under terms such as boot camp. She found what seemed like the ideal solution: a "behaviour modification" school in Costa Rica for struggling teens. The Web site for...