The "one class-one teacher" model was the central organising principle of primary education for most of the last 150 years.
The idea is adored by parents who, correctly, see strength in the idea that one teacher will spend every school day of every year getting to know their kids. Teachers love that idea too. To a point.
The fact is that when I started out, this idea had gone too far in too many schools: the best teachers were believed to be the ones who isolated themselves, who never opened their door during a lesson. You could succeed or fail without anyone knowing. More often than not, you failed.
Times, thankfully, changed. In recent years, the concept of a teacher alone with his or her class has correctly been challenged.
We now accept the benefits of teaching assistants, higher-level TAs, team-teaching and the rest, because pupils have a wide range of needs both educationally and emotionally and no one teacher can do it all.
Where there's money, specialist teachers play an important part for sport, for languages and sometimes for the arts and science. Into this mix, we might throw in wellbeing teams supporting the complex needs that our pupils display.
In the best-run schools, the needs of children are put in the middle of the structure, which balances the brilliance of the essential classroom teacher while also building a culture of teamwork and support around them.
And yet austerity and funding cuts are returning schools to the bad old days where teachers were expected to do it all on their own. All too often, I hear stories of TAs and support staff being shown the door - and other support services being cut as surplus.
Sometimes it seems to me that those who are squeezing public spending are willfully taking us back to "one class-one teacher". Perhaps when they see the consequences of "one teacher-one class", they may loosen the purse-strings a little.
Colin Harris led a school in a deprived area of Portsmouth for more than two decades. His last two Ofsted reports were “outstanding” across all categories