Explore the evidence
7 of 88 decisions · clear everything
Neither acceleration mandates nor delay mandates work — readiness-matched placement does. Push everyone and the median falls; hold everyone back and the top falls.
mixedconf: highgc: lowAlgebra timing — acceleration mandates, delay mandates, and readiness-based placement · math · ages 11–18
Feedback on the task helps modestly; feedback on the person backfires — a stable third of measured effects reverse. The famous 0.4–0.7 number has no computed source.
mixedconf: highgc: lowFeedback and formative assessment · feedback · ages 5–18 · method
The textbook matters at the bottom, not the top: avoid the demonstrated losers; mainstream choices now differ by ~0.02 SD.
mixedconf: highgc: lowMath curriculum choice — how much does the textbook matter? · math · ages 5–14
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
Life-skills courses reliably teach the content and rarely change the conduct; behaviour moves only where instruction sits close in time to the decision, and driver education is worse than nothing.
mixedconf: mediumgc: lowDo life-skills courses — money, cooking, driving, health — change what students actually do? · practical · ages 6–18
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.