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
what are these? →
sortconfidencerobustfragileA–Z
domain
verdict
confidence
layer
Your situation · from the applicability layer — absence means “not yet assessed,” never “doesn’t apply”
who's delivering
group / setting
cost
outcome class

Group within classes or across grades by subject: modest, nearly free wins. Whole-school streaming does nothing, and early between-school tracking harms the bottom.

moderate supportconf: highgc: low
12/1236/48connected:Do career and technical education

Ability grouping and tracking — four practices, four verdicts · grouping · ages 5–18 · structure

Accelerate ready kids: they keep pace with older classmates, bank a year, and show no social-emotional harm at 50. The gifted label itself does nothing; the content does.

moderate supportconf: highgc: medium
8/830/48connected:Algebra timing

Acceleration and gifted programs — the label vs the content · grouping · ages 5–18 · structure

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

The received wisdom that retention is harmful was two measurement errors, not a finding. Fix them and the achievement effect is zero — but the grade at which you hold a child back decides everything.

mixedconf: mediumgc: low
19/1936/48

Grade retention — holding a child back versus promoting, and test-based promotion policies · retention · 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.