They want more frequent reports with more honest and critical information about how their children's performance compares with others'.
They also complain that parents' evenings are chaotic free-for-alls "like rugby matches" which offer no real chance to discuss pupils' progress, says the survey from the charity Research and Information in State Education which was carried out at Bristol University.
It reveals that today's reports are very different from those of 30 years ago when they were little more than lists of test scores and class positions.
Now just 16 per cent report on pupils' positions within groups. Parents complain of "a culture of non-competitiveness". Reports, they say, are too bland and vague. "While parents appreciated that children needed to be encouraged, they felt it was unhelpful to them if this was at the expense of honesty.
"It was often felt that negative comments were hidden ... Parents needed to look out for subtle indicators; for what isn't mentioned as much as what is." This decoding, says the study, is more difficult for those whose children have the most difficulties.
The study of 200 schools and 70 detailed interviews with parents found big variations in the frequency of reports. A fifth of schools send only one a year whereas some schools send out four or five a year.
Parents feel that a report at the end of the year often comes too late to help a struggling child. Their appeal for more written reports comes as ministers are trying to cut school red tape by sending out guidance which suggests reports should be produced just once a year - the legal minimum.
The guidance is being sent out in response to campaigns by teachers' unions to cut teachers' workload.
Parents are even more critical of parents' consultation evenings than they are of reports - and those whose children need most help are the least likely to attend.
Despite all the talk of parents and teachers as partners, says the study: "Most of the parents did not feel they were taken seriously or even welcomed." Some felt patronised and humiliated.
One parent said: "They're a bit of a waste of time. I go on every opportunity and they say yes she's fine, she's fine. We queued up for that, three- quarters of an hour."
Ministers are due to consult later in the year about how school reports may be improved.
The study concludes that teachers should stop worrying about discouraging pupils by making negative comments: "There seems little to be gained by giving parents false impressions of their children's achievements at school." It also suggests that reports should include targets for each pupil.
Parents' evenings should be moved to the start of the year and used to clarify the year's plans and set targets with parents. They should be spread over two consecutive nights for each year or during the day at weekends or during half-term, even if that means more work for teachers.Reuse content