As districts tighten budgets, instructional coaches are often among the first positions cut. What might schools lose when that happens?
A meta-analysis of 60 rigorous studies of instructional coaching from researchers at Harvard and Brown Universities found that the effects of coaching on teaching practices and student achievement amounted to “as much as, or more than, the difference in effectiveness between a novice teacher and a teacher with five to 10 years of experience” (Kraft et al., 2018). Specifically, that translates into moving a teacher from the 50th to the 69th percentile of instructional practice and moving average student achievement from roughly the 50th to the 57th percentile—gains comparable to comprehensive school reform, class-size reduction, and high-dosage tutoring.
These findings make a compelling case for coaching, yet the majority of studies in the sample (34 of 60) involved fewer than 100 teachers and focused predominantly on literacy instruction. Effects declined substantially in larger implementations, which suggests that maintaining coaching quality at scale may be more difficult than in smaller pilots.
A RAND study of 20 Chicago public schools (Mihaly et al., 2022) illustrates this challenge. In each school, one to three teacher leaders were trained to coach one to five colleagues, but after two years, the program produced relatively modest effects. Researchers observed substantial variation in coaching time and declining participation, illustrating the difficulties of maintaining implementation quality at scale.
What do these findings mean for educators? For starters, instructional coaching can be a valuable investment. That said, leaders need to be strategic in how they scale the program:
- First, start with a strong professional learning program. Notably, studies in the meta-analysis that paired coaching with teacher training tended to produce substantially larger effects.
- Second, reserve expert coaching for high-need areas. Given the challenges of scaling, it makes sense to target the areas of greatest need, such as supporting novice teachers and instruction in key subjects, such as reading.
- Third, encourage peer coaching. Research from Bruce Joyce and Beverly Showers (2002), often cited as evidence for instructional coaching, found strong effects for true peer coaching—teachers learning and working together as equal peers, receiving and providing feedback to one another.
So, in an era of budget tightening, it may still be possible for all teachers to benefit from coaching when leaders build a foundation of strong professional learning, target support where needed most, and ultimately, develop all teachers as coaches for each other.
