Parents were deserting the school. Pupils, many from the local estate or short-term housing, were being served by a succession of supply teachers and only a handful were achieving the results required of their age group.
Now, the school has pushed its way up from the bottom of the borough league table to join its best performers. Three-quarters of its 11-year-olds this year achieved the required level in maths and its scores suggest pupils make better progress than similar intakes nationally.
At Montem more than half the pupils are eligible for free school meals. The measure of its success is not only that results have improved radically over the past few years, but that these results are better than other schools in the area with a far more prosperous intake.
When Ms Seifert arrived afte 15 years as head of Thornhill - a primary prized by Islington's middle-class parents - she found a school where teachers had low expectations of pupils and classrooms were poorly equipped.
"It was a matter of restoring order and getting systems into place. No one had cared about the place. Children had been provided with the cheapest books and the worst equipment," she says.
She makes her task sound deceptively simple. "The first issue to tackle was the children's behaviour. They didn't sit down in class. They didn't listen.
"There was a school rule that said when children felt angry they could get up, leave the class and go for a walk round the school. There were lots of children walking round the school," she says.
The one bonus was a bank balance of pound;122,000, now spent. Almost all the classes have a learning assistant and the school has an information technology suite.