There has been a growing increase in the numbers of STEM professionals who choose teaching as a second career for reasons such as dissatisfaction with their existing work situation, desire for life-work balance or a desire to make an impact. How do these teachers adjust to the teaching profession? What do they bring from their life and work experience? How effective are they as teachers? These are the questions that are being researched here with a group of 18 STEM career changers who enrolled in a post-baccalaureate program offered at an urban university in Philadelphia.