This study examined effects of teacher characteristics (gender, teacher education and certification, class management skills and job satisfaction) and teaching styles on indicators of good classroom practice in mathematics classes in secondary education by means of multilevel analysis. The study reveals that the presence of effective classroom practices can be explained by a learner-centered teaching style and by good class management skills. Furthermore, it was found that teachers with a high level of job satisfaction give more instructional support to their classes, especially to classes from a low-ability range, than teachers with a low level of job satisfaction.