Ask a school owner when they plan to move off spreadsheets and you usually get a number back. "When we hit 300 students." "When we open the second branch."
The number is almost always wrong, because the thing that breaks is not the size of the sheet. It is the number of people writing to it.
One person, any size
A single administrator can run a genuinely large sheet. They know that the yellow rows mean unpaid, that column M is out of date, that Miss Anna's Tuesday class actually moved to Wednesday in March but nobody edited the header. The sheet is not really the system. Their memory is the system, and the sheet is a set of notes they keep for themselves.
This works, and it works better than most software vendors like to admit. If you are one person running one campus, a spreadsheet you understand beats a tool you half-configured.
Two people, and the first silent failure
Add a second person and the notes have to become a language. Now "paid" has to mean the same thing to both of you. Does it mean the parent sent a transfer screenshot, or that the money is in the account, or that a receipt was issued?
Nobody sits down to define this. You discover the mismatch about six weeks later, when a parent produces a screenshot for a payment your books never recorded, and both of you are certain you were right.
The sheet cannot help here because a spreadsheet has no opinion about what a cell means. It stores what you typed.
Three people, and the sheet loses
At three, someone is always editing. Two people open the same file, one of them keeps a local copy "just for a second", and a week of attendance disappears without a single error message. That last part is the real problem: nothing tells you. There is no alert for a row that was overwritten. You find out when a parent asks why their child is marked absent for a class they attended.
By this point the school is usually not big. Three staff and 120 students is enough. Owners who wait for a student-count milestone spend a year and a half in this state, quietly absorbing the cost as "we're just busy".
What actually costs you money
Look for these, not for a headcount:
- Two versions of a number in one meeting. Someone says revenue was X, someone else says Y, and both have a file open.
- A task that only one person can do. If invoices go out only when a specific person is in the office, the sheet has become their sheet.
- Follow-ups that depend on remembering. Trial students who never got a call. Overdue invoices nobody chased. These do not appear as errors, only as a slightly worse month.
- Reconstructing the past. Being unable to answer "was this student here in March?" without opening four files.
Any one of these is more expensive than the software you are avoiding.
The honest counter-argument
Moving is not free. You will spend a week getting data in and another two weeks with staff who preferred the old way. If your school is genuinely one person and one campus, and none of the four signs above are true, keep the sheet and spend the money on marketing instead.
But if you recognised two or more of them, the sheet is already costing you the price of a subscription every month. You are simply paying it in evenings and in parents who did not come back.
If you want to see what the alternative looks like without committing anything, the product tour uses realistic school data — including the invoice nobody paid and the room booked twice.