The purpose of this study was to understand the relationships between mathematical content knowledge, perceptions of teaching self-efficacy, and attitudes toward mathematics in one cohort of Teach for America teachers who took the New York State Content Special Test in mathematics at the start of their program, and a mathematics attitude instrument taken before and after their first year teaching while taking graduate courses in a teacher education program. Additionally, teachers completed a self-efficacy instrument in their second year of teaching and graduate coursework. The major finding revealed that mathematical content knowledge was related to attitudes toward mathematics, and attitudes toward mathematics were related to perceptions of self-efficacy. It was found that teachers with mathematics related majors had higher mathematical content knowledge than did business majors, but similar levels of self-efficacy. Liberal arts majors had similar content knowledge and levels of self-efficacy as did mathematics related majors.