But cataloguing trainees as people who have come to take more than they can give might mean missing out on a rich source of human potential that could greatly enhance the life of a school.
As someone who regularly selects trainees, I am struck by the increasing number of graduates who have stepped off the "school-university-school" conveyor belt and decided to give the wider world a look before heading back to the classroom. To give two recent examples: a young woman who developed her skills as a teacher of reading while working in Kenya with Voluntary Service Overseas, and a young man who used to be an ICT manager and a DJ on a Czech radio station.
Academically, graduates bring a wealth of expertise: this one wrote his Master's dissertation on the literature of conflict; the eyes of that one light up at the sight of an Anglo-Saxon manuscript; another is a nifty exponent of Michael Jackson's moonwalk, a skill acquired in her dance training.
How can schools and teachers benefit from all this talent? First, by applying the principles of differentiation to trainees as rigorously as to their pupils: find out what each one can do, so skills and expertise that might otherwise remain hidden can be celebrated and brought to the service of the school.
And second, by thinking in terms of "critical mass". Why not invite a PGCE subject cohort to school at the same time? They might work with a whole year group (and their teachers) on a specific focus, such as cross-curricular literacy; or they might provide intensive one-to-one support for a selected group of pupils.
The school can also come to the trainees. We are fortunate in York to have an LEA that encourages imaginative collaborations of this kind. This summer, our PGCE secondary English group liaised with the local authority co-ordinator for the gifted and talented to provide a range of workshops on various aspects of English designed for high-achieving Year 10 pupils.
During lunch, the teacher trainees took the pupils on a tour of the campus and talked to them about studying English at university. The day appears to have been a great success for both groups.
So greet those fresh-faced graduates when they come through the door and, in the words that US President John Kennedy almost used: "Ask not what you can do for your trainee teachers; ask what your trainee teachers can do for you."
Nick McGuinn is course leader for PGCE English at the department of educational studies, University of York