The Evidence on Teaching

Explore the evidence

6 of 88 decisions · clear everything

Survives the gold standardIndependent, durable, rigorousThe debunked shelfCheap winsFor parents at homeFamous numbers, deflatedWhere we admit ignoranceThe terrain
evidencealldrop DA–BA only
evaluatoranyno dev-ledindependent
durabilityanyfollow-up≥1yr≥2yr
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Your situation · from the applicability layer — absence means “not yet assessed,” never “doesn’t apply”
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group / setting
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Feedback on the task helps modestly; feedback on the person backfires — a stable third of studies reverse. The famous 0.4–0.7 number has no computed source.

mixedconf: highgc: low
18/1812/48connected:Retrieval practice (the testing efDoes teaching music produce musicaPlacement and mastery diagnosis

Feedback and formative assessment · feedback · ages 5–18 · method

Mastery learning moves tests of what it taught (~0.25) and barely moves independent measures (~0.05) — and time-to-mastery gaps widen, converting ability differences into time.

mixedconf: highgc: low
6/69/48connected:Does educational technology raise Retrieval practice (the testing efPlacement and mastery diagnosis

Mastery learning (teach → test → reteach to criterion → advance) · mastery · ages 6–18 · method

Immersion costs nothing in English and buys a little — a lottery puts English reading 0.13-0.22 SD ahead by grades 5 and 8 — but no lottery has ever measured how much of the second language students actually learn.

moderate supportconf: mediumgc: low
8/824/48

Does dual-language immersion work, and is the gain in the second language or in English? · foreign-language · ages 4–18

Explicit form-focused teaching beats pure exposure, so the archive's negative verdict on L1 grammar does NOT transfer — but the effects are measured on the taught forms, immediately, mostly on adults.

mixedconf: mediumgc: low
11/1118/48connected:Does teaching grammar improve chil

Comprehensible input or explicit grammar teaching — which builds a second language? · foreign-language · ages 4–18

Near-zero in primary and almost entirely correlational in secondary. The causal base is three small trials; what the homework IS beats how much of it there is.

mixedconf: mediumgc: medium
16/1629/48

Homework — effects by age and by dosage · homework · ages 5–18 · structure

Attainment falls steadily with age of first exposure, but the sharp critical period is contested and an earlier classroom start buys nothing durable: start young for immersion, not for two lessons a week.

mixedconf: mediumgc: medium
14/1424/48

Is there a critical period for learning a second language, and when should a child start? · foreign-language · ages 4–18

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