Lost Learning Hub

Whole-School Lost Learning Calculator

Section 01

Your school

Set the size and shape of the school you're modelling.

Number on roll

Total pupils on roll across the school, year group or cohort.

School days per academic year

Typical UK statutory minimum is 190 days.

Taught hours per school day

Directed teaching time, not the total school day.

Lessons per school day

Number of discrete lesson periods.

Average attendance %

Whole-school average attendance.

Section 02

Whole-school behaviours & interruptions

Enter whole-school totals and averages for a typical academic year.

Average disruption minutes per lesson

Low-level disruption and off-task time affecting every pupil, in every lesson.

Total removals per year

Total number of removals recorded across the whole school in one academic year.

Hours lost per removal

Average duration of each removal.

Total suspensions per year

Total number of suspensions issued across the whole school in one academic year.

Average suspension length (days)

Average length of each suspension in school days.

Average late marks per day

Total number of late marks recorded across the whole school on an average day.

Average minutes late per arrival

Average minutes late per affected lesson.

Section 03

Whole school results

Live totals scaled across your entire roll.

Total learning hours lost

139,237

hrs

Equivalent school days lost

27,847

days

Equivalent school weeks lost

5,569

weeks

Equivalent school years lost

146.6

years

Average loss per learner

154.7

hrs / pupil / yr

% of curriculum lost

16.3%

Whole-school learning time

Remaining vs lost (this year)

Contribution of each factor

Whole-school hours lost, largest first

Section 04

Detailed breakdown

Per pupil and whole-school totals for each factor.

Factor	Hours per pupil / year	Whole-school hours / year	Share of total loss
Absence	66.5	59,850	43.0%
Disruption	73.6	66,263	47.6%
Removals	6.0	5,400	3.9%
Suspensions	2.3	2,025	1.5%
Late Arrival	6.3	5,700	4.1%
TOTAL	154.7	139,237	100.0%

Your whole-school results

Across a roll of 900 pupils, this school loses an estimated 139,237 hours of learning in a single academic year.

That is the equivalent of 27,847 school days, 5,569 school weeks, or 146.6 full school years of curriculum time — with an average loss of 154.7 hours per learner.

This represents 16.3% of the total curriculum offer, or 17.5% of the time pupils are actually present in school.

Small, everyday interruptions compound quickly at scale. Attendance strategy, behaviour systems and lesson-level routines are the highest-leverage places to recover this time.

The BelongED Whole-School Lost Learning Calculator is provided for illustrative and strategic planning purposes. Figures should be interpreted alongside professional judgement and local context.