Private schools have been hiring A.B.D.'s and Ph.D.'s who show an interest in and some experience working with adolescents. They are particularly eager to hire math and science teachers. If you are willing to venture into the business world, you might well gravitate to the field of training and development. Training can include everything from technical and substantive education to writing and presentation skills to career development. It is also possible to gratify your love of teaching more indirectly within the for-profit sector.
Sales is another route.
For example, I know a biology Ph.D. who came back to academic research after a career at Merck and an economist who took a tenured university professorship in health policy after a 20-year career in a think tank. In general, if you have outside industry or government experience, it is easiest to return to an academic position in a professional school. Outside experience is also viewed as a plus for upper-level academic administrative positions. Margaret Newhouse is assistant director of career services for Ph.D's at Harvard University. Even though she cannot answer e-mail personally, Ms. Newhouse appreciates comments, stories, and suggestions.