Fine by me. You can learn a lot from people who know the difference between financial products. But do you think a person like that has changed much over the years? No, neither do I. The tendency to be motivated by money will have been there at the start. (Syed, of the BBC’s much-missed The Apprentice, thought, at 31, “pound;100,000 salary is not enough but it’s a good place to start.”) Do you think Syed - or any of the would-be apprentices - is likely to have considered teaching as a whole-life career?

Neither do I. If money is your prime motivator, you don’t go into teaching.

So why does anyone think that performance-related pay will improve the quality of teaching? It’s a question asked by Jeffrey Pfeffer and Robert I Sutton in a new book from Harvard Business School Press, with the uncompromising title Hard Facts, Dangerous Half-Truths and Total Nonsense.

The authors demolish the case for linking pay to performance in school, and sum it up thus: “Evidence shows that merit-pay plans seldom last longer than five years and that merit pay consistently fails to improve student performance. The very logic of merit pay for teachers suggests that it won’t do whatit is intended to do, or do it very well.”

That doesn’t mean we shouldn’t ever reward teachers who go the extra mile.

One of my pleasures as a governor was to find small sums of money to show our recognition of, say, a teaching assistant’s work with children in the holiday, or making the school garden into a rich learning resource.

One-off or occasional payments for teachers and TAs have become a theme in my recent visits to schools. In one, some staff were receiving an honorarium for their part in a special project. In another, talks were going on with the authority’s auditor to discover what might be possible - and legal (never a bad idea). Sums were always small, and thought of as acknowledgements or rewards, never as incentives. To suggest that anyone might work harder just to get payments would be insulting.

Pfeffer and Sutton have a true story that shows how such rewards should work. A family goes into a menswear shop for dad to buy a jacket. An employee comes to do the “Suit you, sir” stuff. Another takes the kids to a playroom. When it’s time to go, the kids don’t want to leave, so the couple stay a bit longer and buy more clothes. It’s effective teamwork, but in the usual sales setting the guy entertaining the kids wouldn’t get commission.

In this shop, though, there is no sales-based commission.

Instead, everyone in the team gets, on top of their salary, small monthly payments based not on sales but on how well they minimise the number of items lost or stolen. There are three levels of payment - zero, $20 (pound;10) and $40. The amounts - paid in cash - have been thought out so as to bring on a smile but not distort established working patterns. “The focus remained on the celebration of the store’s achievement and the spirit of camaraderie, rather than the money.”

As a head and a chair of governors, I’ve done more than my share of struggling with inadequate budgets, but never have I felt that we couldn’t afford a handy little sum to acknowledge a person’s special contribution and brighten their day. It will be repaid to you with handsome interest, I promise. But I repeat: always check with the payroll and audit people.

Gerald Haigh is a former headteacher