The Association of Secondary Teachers has criticised plans to make statistical information on schools available to parents for the first time later this year.
The first batch of figures is due to be published on the Department of Education's website by Easter, with hundreds more to be made public by December.
The ASTI said today that teachers feel the system of compiling these reports is too bureaucratic, especially in light of serious inadequacies in education funding.
John Whyte, the association's general secretary, said teachers should be devoting more time to students rather than being asked to compile statistical information, most of which is already available.
"This will involve schools in preparing more documents when all our efforts should be put into the classroom," he said.