A class set of thirty graphing calculators is a four-figure purchase, and in most maths departments it is guarded by a paper grid taped inside the cupboard door. The units are identical, they fit in any blazer pocket, exam season scatters them across the building, and one or two fail to come home every summer - which nobody can prove, because the grid has said “Set B: 30” since the day it was printed. The fix costs almost nothing: a number on every unit, a recorded loan for every unit that leaves the room, and a count that happens at moments that matter.
What you will learn
- Why class sets shrink
- Numbering and labelling the set
- What to record per calculator
- Per-lesson sign-out or term loan
- Exam season and end-of-year returns
- Tools that make this easier
- FAQ
Why class sets shrink
Calculators have a specific disappearing act. Every unit looks like every other unit, so nothing identifies the one that left. School-owned and privately owned models sit on the same desks, so units migrate between bags without anyone noticing, let alone lying. Exam timetables move whole sets between rooms in a hurry, with counts nobody has time to take. Battery swaps merge two part-working units into one working one plus a carcass. And because the set was never counted properly, “it was already missing” is both the universal explanation and impossible to disprove. None of this needs bad intent - it needs identical objects, no per-unit identity, and time pressure, all of which a maths department supplies daily.
Numbering and labelling the set
Each unit needs one permanent mark and one scannable one:
- A visible asset number, written large on the back casing - B-01 to B-30 - applied with an engraving tool or a security marker so it survives years of pencil cases. This is the number students quote and slots match.
- A QR label alongside it, which opens the unit’s record for a checkout or return in one scan. Labels on calculators get picked at; place them on the flattest part of the back casing and expect to reprint a few each year.
- The serial number, recorded at purchase from under the battery cover. It is the identifier of last resort: it survives a removed label, separates a school-owned TI-84 from a student’s identical one, and backs an insurance claim.
- A numbered storage caddy or case, where slot 17 holds unit 17. The empty slot is the whole inventory system at a glance.
Tip: count by gaps, not by units. A numbered caddy turns “are all thirty back?” into a two-second scan for empty slots - and tells you immediately that it is B-17 missing, not just “one of them”.
What to record per calculator
| Field | Why it matters |
|---|---|
| Asset number | The visible identity that students quote and caddy slots match |
| Model | Exam regulations and feature differences make the exact model matter |
| Serial number | Survives a picked-off label; separates school units from private ones |
| Home set and room | Which caddy and classroom the unit belongs to and returns to |
| Status | In use, in storage, in repair, retired - so the working count is real |
| Assigned student and loan type | Per-lesson slot or term loan, with a name attached either way |
| Condition and battery state | Dead batteries are the most common “broken calculator” report |
| Purchase date and price | What the set cost, how old it is, and what a loss is actually worth |
Per-lesson sign-out or term loan
Two loan models cover almost every department, and most run both:
- The caddy model, for sets that never leave the classroom: units handed out by slot number, used for the lesson, counted back in before the bell. The set works as a shared equipment pool - low friction, with the empty slot as the alarm.
- The term loan, for exam classes: a recorded checkout of a specific numbered unit to a named student, due back after the final paper, with the student or parent acknowledging the loan and the replacement cost up front - a lightweight equipment loan agreement. Students revise at home with the same unit all year; the department knows exactly who has what.
This is the same issue-and-return discipline schools already run for Chromebooks - calculators just make it harder by being smaller, cheaper-looking and identical.
Exam season and end-of-year returns
Exam season is when sets move most and counts happen least, so put the count where the movement is: when a set goes to an exam room, check the set out to that room or cohort, count units out per session and back in after, by slot. The minutes this takes are recovered the first time a unit is found in an exam hall drawer in October with no way home.
At year end, the term-loan due dates produce an overdue list with names on it - work it while students are still on roll, because recovery afterwards is close to zero. Then report properly: because the register holds purchase dates and prices, “we lost two units from Set B, costing this much, and here is who never returned them” replaces “we probably need more calculators”. That sentence is what gets replacement budget approved, and what makes any charging-for-losses policy fair rather than arbitrary. Replace lost units, renumber the newcomers into the empty slots, and the set starts September whole.
Tools that make this easier
The paper grid and its spreadsheet cousin share one flaw: they are not where the calculators are. The grid is in the cupboard while the set is in an exam hall; the spreadsheet says 30 because nobody updates a count column mid-lesson. Records kept apart from the objects they describe go stale - the longer version is in why spreadsheets fail for asset tracking.
AMPthilly gives each unit a profile - asset number, serial, model, status, condition notes - and makes loans recorded events: check a unit out to a named person with a due date, see the overdue list at year end, and keep the full history of every unit across school years. The QR label on the back opens the unit’s record in any phone browser for a check-in or check-out at the classroom door, with nothing to install. The free plan covers 3 users and 25 assets - enough to pilot the workflow on an exam-class loan pool before rolling out whole sets.
FAQ
How do schools keep track of graphing calculators? A number and QR label on every unit, serials recorded at purchase, and a loan model - caddy slots for lessons, recorded term loans for exam classes.
Is it better to loan calculators per lesson or per term? Both have a place: per-lesson caddy sign-out for classroom sets, term loans to named students for exam years. Most departments run the two side by side.
What is the best way to label school calculators? An engraved or security-marked number for permanence, a QR label for one-scan access to the record, and the serial recorded as backup.
What happens when a calculator is not returned? The overdue list names the holder; chase while the student is on roll. A recorded, acknowledged loan is what makes any replacement charge fair.
Should we record calculator serial numbers? Yes, at purchase. The serial is the identifier that survives everything else and settles whose calculator it actually is.
The takeaway
Class sets shrink because identical units with no identity meet busy classrooms and exam timetables. Give every calculator a permanent number, a scannable label and a recorded serial; loan by caddy slot for lessons and by named term loan for exam classes; count by empty slots at the moments sets move. Do that, and the year-end conversation changes from “we seem to be short a few” to a loss report with numbers, names and costs - usually a much shorter list.