Coaching and expert support appeared in 30 of 35 studies, with coached classrooms showing larger gains in a randomized trial¶

Claim · All claims
Evidence · 1 study (2 entries) · review r2 · q2–q4
Currency · newest study 2017 · checked against its sources 2026-10-13 (automated, 2 of 2 entries) · not reviewed by a person

Subclaims¶

Reading the evidence codes

q is the design tier, i the impact, n the sample, and the kind with its r the rigour judged within that kind: what each code means.

This claim: no standardized effect is recorded in observations/ for it yet, so no benchmark reading is possible.

q2 i? Coaching or other expert support was identified in 30 of the 35 studies reviewed. → Darling-Hammond 2017 q4 i? In a two-year randomized control trial of early literacy coaching, classrooms of participating educators showed larger gains on a classroom quality assessment, and children showed significantly larger gains on early language and literacy skills than controls. → Darling-Hammond 2017 (2)

Evidence¶

Darling-Hammond 2017¶

Darling-Hammond, L., Hyler, M. E., Gardner, M. (2017). Effective Teacher Professional Development. Palo Alto, CA: Learning Policy Institute. https://learningpolicyinstitute.org/product/teacher-prof-dev. doi:10.54300/122.311

q2 · i? · review · r2

Coding result across the report's reviewed studies; experts ranged from specially trained master teachers and instructional leaders to researchers and university faculty, delivering one-on-one coaching, group workshops, or remote mentoring.

"The practice of providing coaching or other expert support for educators was identified in 30 of the 35 studies reviewed."

Darling-Hammond 2017 (2)¶

q4 · i? · review · r2

Powell and colleagues (2010) coaching model for early childhood educators: biweekly coaching sessions with university-based literacy coaches over a semester-long program including 16 hours of workshops and seven coaching sessions. The report states children of participating teachers showed significantly larger language and literacy gains.

"A two-year randomized control trial found that classrooms led by educators who participated in this coaching model demonstrated larger gains and higher performance on a valid and widely used early childhood classroom quality assessment than did control group classrooms."

Discussion¶

Teacher coaching raises student achievement on standardized tests by a pooled 0.18 SD across 31 causal studies — the general claim this finding bears on, with the studies behind it
Teacher coaching programs improve teachers' instructional practice by a pooled 0.49 SD across 43 causal studies — the general claim this finding bears on, with the studies behind it
Collaboration appeared in 32 of 35 reviewed studies, and collaborative PD models showed student achievement gains — related
Parent Coaching Outperforms Information Only — related
All 35 reviewed studies used models or modeling, and curriculum without PD support yielded worse outcomes than older curriculum with none — related
Ongoing professional development and mentorship are critical to coaches' growth and confidence in their coaching skills — related
Effective professional development is content focused, active, collaborative, modeled, coached, feedback-rich, and sustained over time — a broader claim this one bears on

Page metadata

Field	Value
`type`	`claim`
`id`	`pd-coaching-expert-support-gains`
`title`	`Coaching and expert support appeared in 30 of 35 studies, with coached classrooms showing larger gains in a randomized trial`
`description`	`Coaching and expert support appeared in 30 of 35 studies, with coached classrooms showing larger gains in a randomized trial`
`status`	`review`
`evidence_strength`	`moderate`
`newest_evidence`	`2017`
`source_checked`	`2026-10-13`
`generated`	by `process:wiki-ingest` on `2026-10-10`
`trust`	unverified — no one has confirmed this page's content
`sources`	2 — `darling-hammond-2017`, `darling-hammond-2017-2`

Frontmatter is the page's machine-readable record — see the Schema & Guide.