Explore the evidence
3 of 88 decisions · clear everything
Survives the gold standardIndependent, durable, rigorousThe debunked shelfCheap winsFor parents at homeFamous numbers, deflatedWhere we admit ignoranceThe terrain
domain
verdict
confidence
layer
Your situation · from the applicability layer — absence means “not yet assessed,” never “doesn’t apply”
group / setting
outcome class
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: lowComprehensible 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: medium16/1629/48
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: medium14/1424/48
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.