The timetable gets weeks of attention. The duty rota is usually built in an afternoon, after the timetable is finished, by whoever drew the short straw — and it is the document most likely to end up on the staffroom wall with someone's name circled.
Rotas are not hard to build. They are easy to build badly: a rota can look reasonable and still send the same six people to the yard every week. This guide is for the person who builds it.
Decide what one duty is
Most schools run two different kinds of supervision and call both "duty":
| Kind | Example | Natural unit |
|---|---|---|
| Whole-day responsibility | First-floor corridor on Tuesday — the teacher still teaches, but is the contact for that floor all day | One duty per day |
| A specific break | Yard at the second break, canteen at lunch — someone physically stands there | One duty per break |
Mixing the units quietly breaks fairness. One teacher covers three breaks, all on Tuesday; another covers one break each on Monday, Wednesday and Friday. Counted in days, the first has one duty and the second three. Counted in breaks, they are level — which is what they are. Write down per area which unit applies.
Start from the building, not the staff list
List the places that need a supervisor — yard, corridors, canteen, bus bay — and for each answer four questions:
- How many people? A large yard may need two; a corridor needs one.
- Which days? A short Friday may have no lunch break.
- All day, or which breaks? The canteen matters at lunch and nowhere else.
- Must the supervisor be free? Someone standing in the yard cannot be teaching at that moment. Someone responsible for a floor usually can.
Then do the arithmetic. An illustrative school: two supervisors in the yard at each of two breaks, one on each of two corridors at the same breaks, two in the canteen at lunch, five days a week. That is 20 + 20 + 10 = 50 duties a week. With 60 teachers, 8 of them exempt, 52 people share 50 duties — just under one each.
Who is actually in the building
Availability for duty comes from the timetable, not the staff list. A teacher whose Tuesday ends after the third lesson cannot cover the lunch break. A part-timer who does not come in on Thursdays cannot cover anything on a Thursday.
A workable rule: a teacher is available from shortly before their first lesson of the day until shortly after their last. Free periods in between count as present — nobody leaves the building between two lessons, and a gap is the most natural place for a duty. (Our piece on teacher gaps and student gaps covers why gaps exist at all.)
The consequence: build the timetable first, the rota second. If the rota has to go out earlier, mark it provisional and rebuild it once the timetable settles.
Put people near where they already are
A teacher who teaches 7B on the first floor on Wednesday is the obvious choice for first-floor corridor duty that Wednesday. One who has to cross the site at a fifteen-minute break has spent the break walking.
Proximity is a good tie-breaker and a bad first principle. Apply it too strongly and the teacher whose lessons are all on the first floor gets every first-floor duty of the week. Fairness first, then proximity.
Part-timers and teaching load
"Everyone does the same number" is simple to check, but not automatically fair: a teacher on a half contract doing as many duties as a full-timer supervises twice as much relative to their hours. Many schools reduce duties for part-time staff, and in some places regulations or staff agreements say how — check what applies to you. The common approaches:
- Equal per head. Easy to verify, easy to argue about.
- Proportional to contract hours. Fairer on paper; needs a rounding rule, because duties come in whole units.
- Equal per head, with a cap for part-timers. A pragmatic middle.
Some schools also count supervision against teaching load. Whatever you choose, agree the rule and write it down before anyone sees names on a rota. A rule adopted after the complaints looks like a concession, not a principle.
Measure fairness, don't feel it
Felt fairness is unreliable. A wet January morning in the yard weighs more in memory than three quiet corridor duties, people remember what they did rather than what colleagues did, and the person building the rota is a colleague too.
So count. Once the rota is drafted, list every teacher on it with their number of duties in the agreed unit, sorted, and look at four things:
- The spread between the highest and lowest count. This should be small.
- Everyone above the fair share — total duties divided by the people on the rota, adjusted by your part-time rule. Each needs a reason, usually availability.
- Everyone on zero — either an exemption that belongs on the list, or someone who slipped through the availability gaps.
- Empty slots. A break nobody can cover is more urgent than a slightly uneven count.
How Bildena plans duties
Duty planning in Bildena is a separate step. It reads the current timetable and never changes it — no lesson is moved to make the rota look better.
What you define. Duty areas, each with the number of teachers it needs, the days it is staffed, and whether it runs all day or at particular breaks (taken from your bell schedule). An area can list the rooms it covers and can require a supervisor who is not teaching at that time. Per teacher you can set an exemption, which removes them from the candidates entirely, or a weekly maximum.
Who is a candidate. From one period before a teacher's first lesson of the day to one period after their last, gaps counted as present. With no timetable yet, everyone counts as available, so a rota can be drafted at the start of the year and rerun later.
What it balances. Our solver, tuned specifically for distributing lessons and duties across a school week, works through a fixed order of priorities:
- Fill every slot. One that cannot be filled is left empty and reported, rather than the run failing.
- Keep everyone at or below the fair share: total duties divided by the number of candidates. This is a strong preference, not a hard rule — thin availability on one day means one extra duty for someone rather than an empty slot.
- Keep a whole-day area with one person for the day instead of splitting it across three.
- Narrow the gap between the most and least loaded teacher.
- Prefer teachers who teach in that area's rooms that day.
A whole-day area counts once per day, a break area once per break. A teacher's weekly maximum is never exceeded.
What you control afterwards. The result is a board with days as rows and areas as columns. Drag a teacher elsewhere or pick one for an empty slot; the picker shows each teacher's duty count and whether they teach near that area, and greys out anyone already on duty that day. Anything placed by hand is pinned and survives the next run. A balance panel lists every candidate's count and flags those with none, and the rota exports to PDF or Excel with that table underneath.
What it does not do. The fair share is the same for every candidate: Bildena does not currently scale duties by contract hours or teaching load, and the priorities above are not adjustable. If part-timers at your school do fewer duties, today you express that with a weekly maximum on each of them.
A short checklist
- Decide the unit for each area: per day or per break.
- List areas with head count, days, and whole day or specific breaks.
- Agree the exemption list and the part-time rule, in writing.
- Build the timetable before the rota, or mark the rota provisional.
- Draft, then count: spread, above the share, on zero, empty slots.
- Publish the counts alongside the names.
None of this makes duties popular. It makes them defensible, which is the most a rota can realistically aim for.
In Bildena, duty areas are set up alongside rooms, and the rota has its own board next to the timetable — it reads the timetable and leaves every lesson where it is.