But what of the rest? Chaotic, divided households - brimming over with tension and recrimination - will either ruin some children’s classroom performance, or make school a welcome respite.

Local authority social workers are lucky - yes, lucky - to have an overview. They can get through doors normally closed to other professionals. They can also work one-to-one and intensively: time denied to most state-sector teachers.

It still seems absurd that any teacher could be envious of the humble social worker. Does not this home missionary unceasingly complain about high caseload, long hours, violent customers and a mountain of paperwork?

Yet there are considerable advantages, more now than ever before, to being the door-knocker. And don’t believe anybody who says door-knocking is more co-ordinated these days. It is not. A family due for care proceedings, could be visited in a single week by the solicitor for themselves, the solicitor for the guardian, the guardian, the psychologist, the family support worker, the probation officer, the home-care aide and the allocated social worker.

All these people, and more, want to find out how a family ticks and whether it is safe to leave young people in that environment. The door is sometimes closed, or slammed in one’s face. More often, families at risk let all these outsiders in with resignation. World-weariness cannot get worse.

Social workers prefer to deny that sheer curiosity is a main factor in their attempts to understand the reconstituted family.

Surely there must be lots of two-birth-parent families calling upon the services of their social worker. Not in significant numbers. Reconstituted families: lone, gay or foster parents, grandparent-carers, step families, cohabiting couples and complex amalgams, need more disentangling.

There are thousands of reconstituted families who make no extra demand on courts or social workers, but risk does increase in the few reconstituted families where children have proved an added burden, where they have been left behind or where they have suffered menal, physical and sexual harm. That harm is quite dramatic: the stuff that dramas would be written about.

Social workers are usually not dramatists but their door-knocking soon becomes surreal in that they hear about some very degrading behaviour and some very valiant attempts to throw officials off the scent. Children are amazingly loyal to the carers they know best.

It is a shame that teachers only see social workers when they are “taking the side” of some disruptive child, or when teachers attend child protection conferences.

Teachers at all levels would benefit from a fortnight’s secondment to an area social services office. The grass really can be greener than in the school corridor. Teachers might be astonished at how plump some pupils’ social work records are: social workers still use paper rather than electronic storage. There can be as many as four huge volumes for a single child - every twist of fate in an unhappy life so far. Chronologies alone can run into 10 pages.

Then teachers might be surprised how empty some pupils’ lives are after exclusion from school. Apart from a couple of hours’ home tuition, the expelled child flounders, filling blank mornings, afternoons and evenings in not very stable home surroundings. Temptations are many, pocket-money stretched.

Most school non-attenders are little trouble to anyone. But risks such as drugs, offending and victimisation can never be ignored.

Thrill is not too strong a word at seeing the new orders made possible by (the 1999) Youth Justice Act. Reparation Orders, Parenting Orders, Child Safety Orders and Youth Panels will all revolutionise social work with unsettled teenagers.

In summary, social workers now have more time, greater power, wider overview, (potentially) increased job satisfaction, and more consistent entry into home and peer-group than that enjoyed by many teachers.

And crucially, there is no exact equivalent of the Office for Standards in Education or performance-related pay. Social workers faced their biggest changes in 1971 and 1991, not monthly. And trouble never came in a multiple of 30.

Godfrey Holmes taught religious studies in Nottingham before becoming a social worker.