cc Managing Difficult Behavior in Children 2-12; The best-selling, award-winning discipline program used by millions of parents and teachers; Kids are just kids! In addition to being delightful, charming and affectionate, children can also present their adult caretakers with a steady diet of difficult behavior: whining, arguing, teasing, fighting, yelling, tantrums and pouting. For this reason, Dr. Thomas W. Phelan designed the 1-2-3 Magic program to bring practical, easy-to-use discipline techniques to families and educators.