Teacher Coaching Can Boost Instruction and Student Achievement. But Can It Be Scaled Up?

One-on-one teacher coaching generates meaningful improvements to both classroom instruction and student achievement, according to a newly published meta-analysis of existing research. But there’s a tricky caveat: Efforts to expand coaching programs on a wider scale might only dilute their value, the authors find.

Key takeaways from this study include the following:

  • Coaching programs tend to enhance both the quality of teaching and student achievement, though the former much more than the latter.
  • The impact on student achievement of implementing an effective coaching regime compares favorably with other reforms, such as student academic incentives, merit-based pay, and extended learning time.
  • The benefits to instruction are described as larger than the difference in quality between a novice teacher and a more experienced colleague.
  • High-quality programs tend to combine group training sessions with individual consultations between teachers and coaches.
  • In terms of student achievement, content-specific programs seem to work better than generalized coaching.
  • Quantity matters less than quality. The studies show that more hours of coaching aren’t correlated with greater effects.
  • Coaching works best in school environments that make a lot of room for experimentation and critique.

But the most important variable is clearly size. Expanding a coaching intervention is consistently shown to limit its effectiveness. The authors separated the programs into smaller examples (less than 100 participants) and larger ones (more than 100). The smaller programs’ impact on instruction was nearly double that of larger programs. For student achievement, smaller programs were nearly three times as effective.

It’s difficult to recruit and train large numbers of teacher coaches, the authors explain. Standardizing the programs across large schools, districts, and even entire states (one study measured a literacy initiative that deployed 2,300 coaches across Florida; results were almost nonexistent) can decrease the flexibility necessary to improve performance among teachers of different skills and specializations.

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For the study, see: https://scholar.harvard.edu/mkraft/publications/teacher-accountability-reforms-and-supply-new-teachers