Think of a lay inspector, in spades, and you are half way to defining the approach of Sir John Harvey Jones, who in a new series, Troubleshooter Returns, visits three schools in an exploration of contemporary education.

Or rather four, because right at the beginning, after making a vituperative attack on the memory of his own prep school in Deal, he actually turns up there with a JCB and gleefully knocks it down, paying particular attention to the head’s study. Admittedly the building was derelict, but the point is well made.

Sir John, following up his thesis that “for far too long our education system has concentrated on the few and failed the vast majority”, goes first to Lawrence Weston, a Bristol comprehensive lacking in just about everything morale, pupil numbers, academic results. From there he calls at Clifton College, a public school that was the alma mater of Henry Newbolt (“There’s a breathless hush in the close tonight, ten to make and the last man in . . .”) to talk with senior pupils.

And finally he makes a return visit to Garibaldi School, a comprehensive in Mansfield which he has been helping for some years and which, according to Sir John, was once locally celebrated in a poetic style rather different from Newbolt’s: “They used to say ‘red sky at night, Garibaldi’s alight!’”.

Lawrence Weston, he finds, has lovely but unmotivated children, and teachers who plainly do not all share senior management’s belief in the possibility of improvement. Sir John confronts the head, Chris Lindup, with this in a meeting. The head, a palpably nice man with real affection for his charges, finds some of Sir John’s findings uncomfortable. “I feel a bit defensive when you say things like that,” he says unhappily at one point, while Sir John’s own voice-over to one of the head’s replies is “to me that sounds like waffle”.

His advice, essentially, is that the headteacher should focus on some attainable shared targets and then celebrate their achievement. He also takes Chris Lindup with him to Garibaldi, now thriving, to see the improvements made there by head Bob Salisbury. Then, a year on, we see Lawrence Weston again where Chris Lindup is walking a little taller among his now uniformed and measurably more successful pupils.

And Clifton College? In some ways his meeting there is the most depressing experience of all, for him and for us, mainly because of the way these assured and intelligent pupils unanimously reject any idea of wanting to work in industry. “Industry is not seen as intellectually taxing,” says one young man, sublimely unconscious of what it might mean to offer such a view to, of all people, Sir John Harvey Jones, whose inward seething is plain to see.

Sir John finishes the programme by debating teacher training with his student teacher granddaughter Abigail and two of her friends. Even though it is captivating to see the pride with which Sir John watches Abbie in the classroom, this section is unconvincing. Sir John should certainly get involved in the teacher training debate, but he needs to visit the training institutions and give them the Lawrence Weston treatment. To do it just by listening to the worries of three students is simply unfair and a bit unworthy of the standards of the series.

Nevertheless this is a very watchable programme with a real sense of urgency about it. Sir John’s charm, his easy relationship with children and his evident understanding of the teacher’s task should win over any doubting teacher viewers.