Explore the evidence
7 of 88 decisions · clear everything
High-dosage tutoring is education's most reliable lever: ~0.29 SD in trials, ~0.2 well-scaled — not Bloom's 2σ. Groups of 3–4 work; 1:1 is unnecessary.
strong supportconf: highgc: lowTutoring — the honest effect, the Bloom 2-sigma myth, and what survives scale · tutoring · ages 5–18 · method
Unassisted discovery loses to explicit teaching; well-scaffolded guided discovery beats both. The operative variable is guidance, not ideology.
moderate supportconf: mediumgc: lowExplicit instruction vs discovery/inquiry — how much guidance? · instruction-style · ages 4–18 · method
Novices learn faster studying solutions than solving problems — then the effect reverses with expertise. Use worked examples early; fade them.
moderate supportconf: mediumgc: lowWorked examples (studying solutions vs solving problems) · instruction-style · ages 10–18 · method
A missed day costs little (~0.005 SD); interventions reliably buy days back cheaply, but nobody has shown the recovered days move achievement.
mixedconf: mediumgc: mediumChronic absenteeism — does raising attendance raise achievement? · time · ages 4–18 · input
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: mediumHomework — effects by age and by dosage · homework · ages 5–18 · structure
Classroom order is causally worth a great deal — one disruptive peer costs classmates 3% of adult earnings — yet no branded behaviour programme reliably delivers it and exclusion makes things worse.
mixedconf: mediumgc: lowHow should a school run its classrooms and its discipline system? · behavior · ages 4–18 · structure
Taking time away hurts measurably; adding it back buys almost nothing. The return per hour is ~0.02-0.03 SD, concave, and near zero in disorderly classrooms.
mixedconf: mediumgc: lowLength of the school day and year, time-on-task, extended time, and summer · time · ages 4–18 · structure
The URL is the state — any view you build here is a permalink you can hand to someone mid-argument.