At the union's annual conference, which began yesterday in Blackpool, there will be demands for strikes over pay and class size and for a boycott of national testing. If Mr McAvoy and his executive have their way - and they usually do - few of these threats will result in action.
During the last few years the mood of the union, which held a prolonged and damaging strike over pay in the mid-Eighties, has been transformed.
Mr McAvoy, the union's general secretary, makes it clear that he supports strike action only in the very last resort. Otherwise, he believes, the alliance built by teachers with parents and governors during recent months over spending cuts will crumble and with it the best chance of persuading the Government to spend more on schools.
Mr McAvoy said: "We have a better rapport with parents, governors and politicians than we have had for many years. Much of the argument at conference will be about whether that is a more profitable way forward than disrupting education.
"In the last few months we have seen the extent to which the Government has had to react to a partnership of parents, governors and teachers. Conference delegates have to think very carefully about widespread industrial action.
"It would be wrong to assume you can transfer the support we have from parents and governors over funding to other issues which they may see as purely teacher issues. Strike action has to be taken only when you are fairly confident that parents and governors will see it as a last resort."
There has been local action over cuts by his members in some areas, perhaps because they believe they have the support of parents. Generally, however, he thinks parents believe they can still persuade the Government to change its mind over funding.
Since the union agreed to call off its boycott of national tests earlier this year in return for a review of testing, critics have accused Mr McAvoy of enjoying too cosy a relationship with Gillian Shephard, the Secretary of State for Education.
They say the union has deliberately softened its line towards the Government in the hope that the review will recommend moves away from external tests towards teacher assessment.
Mr McAvoy says: "We have been just as critical of Gillian Shephard as we have of her predecessors, particularly over funding."
Yet he pays Mrs Shephard compliments he would never have bestowed on previous secretaries of state for education. "She understands education. She has been in the service and can see it from a teacher's point of view.
"In that sense she is easier to deal with. There is a willingness to recognise defects, if not in the policies themselves, at least in their application."
He points to her insistence on more funds for ethnic minority children and her recognition that school inspections by the Office for Standards in Education need to be less punitive.
As for the Labour Party, he is adamant that the union's policy of partnership rather than strikes has nothing to do with the need to avoid bad publicity for Labour in the run-up to the general election.
"The Blair Labour Party seems to want to distance itself from organisations with which it might in the past have had a special relationship.
"Sometimes I wonder whether we are being drawn in to criticise the party so it can say that it does not have a special relationship with the NUT. I am not certain teachers' strikes would be detrimental to Labour."