In addition, Sanders and Horn (1998) found that the single most important factor in student academic achievement is the classroom teacher. Therefore, it seems that identifying the characteristics that make teachers most effective should be a high priority for school administrators, legislators, teachers, and students alike.
There has been much research conducted about teacher effects such as age, experience level, college coursework, attitudes, and teaching styles on students' academic success and learning. For example, in a review of past literature, Wayne and Youngs found that teacher college ratings, licensure test scores, degrees, and certification status were positively correlated with student achievement gains. They concluded that students learn more from teachers with higher ratings in each of the stated characteristics (2003). In addition, a study of first-grade teachers found that those who conveyed more positive attitudes and beliefs produced significantly higher achievement gains in their students (Cantrell, Stenner, & Katzenmeyer, 1977). These characteristics account for some of the teachers' influence on students' achievement, but other, less researched teacher qualities may be responsible for this influence as well.
Studies exploring teacher personality effects on student academic success have found that teachers with certain personality