We use a novel database of the preservice apprenticeships ("student teaching placements") of teachers in Washington State to investigate the relationship between mentor effectiveness (as measured by value added) and the future effectiveness of their mentees. We find a strong, positive relationship between the effectiveness of a teacher's…

Stories about the importance of teacher effectiveness for student achievement are currently ubiquitous in the media (Gladwell 2008; Kristoff 2009; Felch et al 2010). Teacher quality is also the focus of significant national efforts and investments. A growing body of quantitative research supports the focus on teacher and teacher effectiveness.…