The Evidence on Teaching

Explore the evidence

8 of 88 decisions · clear everything

Survives the gold standard Independent, durable, rigorous The debunked shelf Cheap wins For parents at home Famous numbers, deflated Where we admit ignorance The terrain

evidenceall drop D A–B A only

evaluatorany no dev-led independent

durabilityany follow-up ≥1yr ≥2yr

what are these? →

Your situation · from the applicability layer — absence means “not yet assessed,” never “doesn’t apply”

who's delivering

group / setting

cost

outcome class

domain skill5

Testing yourself beats rereading — robust in real classrooms; honest durable size ~0.1–0.3 SD, biggest after delay, thinnest on transfer.

strong supportconf: highgc: low

10/1018/48connected:Feedback and formative assessment Mastery learning (teach → test → r Spaced (distributed) practice

Retrieval practice (the testing effect) · practice · ages 8–18 · method

Spacing beats massing at equal total time — the most robust finding in learning science. Space repetitions at ~10–20% of how long you need to remember.

strong supportconf: highgc: low

7/712/48connected:Interleaving (mixing problem types Math-fact fluency and timed practi Retrieval practice (the testing ef

Spaced (distributed) practice · practice · ages 6–18 · method

Teaching coding teaches coding: the one clean school RCT gives g=0.47-0.68. Which approach you pick barely matters, and almost every effect size rests on an instrument the developers built.

moderate supportconf: mediumgc: low

22/2225/48connected:Does learning to code improve gene Talent and trainability

Does teaching programming actually teach programming — and does the method matter? · computer-science · ages 5–18

Mixing problem types helps where confusion is the enemy — discriminating similar categories, mixed math practice — and is useless or worse for facts and prose.

moderate supportconf: mediumgc: low

7/718/48connected:Spaced (distributed) practice Science content sequencing

Interleaving (mixing problem types vs blocking) · practice · ages 10–18 · method

Diagnose what a child already knows: teachers cut 40–50% of curriculum for high-ability children and achievement ROSE. The payoff is skipping, not monitoring.

moderate supportconf: mediumgc: medium

16/1625/48connected:Does educational technology raise Feedback and formative assessment Mastery learning (teach → test → r

Placement and mastery diagnosis — deciding what to teach next from evidence of current skill · assessment · ages 5–18 · structure

Sort by what the software replaces: adaptive drill inside the school day buys +0.05-0.20 SD; a device, a connection or the teacher buys zero to negative; LLM tutors have no usable evidence at all.

mixedconf: mediumgc: low

53/5339/48connected:Placement and mastery diagnosis Mastery learning (teach → test → r Tutoring Class-size reduction

Does educational technology raise learning — CAI, adaptive software, devices, screens, and AI tutors? · edtech · ages 5–18 · structure

Coaching buys ~0.25 SD of score and has for 42 years — a fraction of what's advertised — and none of it is ability. The score moves; the construct doesn't.

mixedconf: mediumgc: medium

20/2036/48

Test preparation — does coaching raise scores, and does a raised score mean raised ability? · assessment · ages 5–18 · structure

Trust the composite; distrust the breakdown. Subtest strengths-and-weaknesses replicate at chance on retest, and most of what people read off a score report is noise.

mixedconf: mediumgc: low

21/2124/48

What a standardized achievement score does and does not license · assessment · ages 5–18 · structure

The URL is the state — any view you build here is a permalink you can hand to someone mid-argument.