A Birmingham-based research project is calling for the role of teaching assistants to be clarified at a time of increased use of them in classrooms.
According to the study, teaching assistant jobs are characterised by "confusion and frustration" and "limited training".
The research, conducted by the city's Newman College of Higher Education, found children, parents and teachers felt teaching assistants to perform a vital role.
But it demanded a rethink of their employment, from the initial creation of teaching assistant posts, to how they should be managed once working in schools.
Professor Stan Tucker, of Newman College, said: "This research is really important when the Government intends to increase the role and status of teaching assistants in the classroom.
"Teaching assistants perform important educational, social care and health functions but often the importance of the work is not recognised," he added.
"Those running schools do not always share a common view on how teaching assistants should be used in the classroom.
"This can lead to confusion and frustration.
"This research highlights the need for greater clarity in terms of the creation of an appropriate job description, better management and more focused deployment."
The research highlighted the need for teaching assistants to participate in work-based training programmes.