He was speaking at last week's conference on promoting partnership with parents in assessment and reporting, which heard that the Executive's curriculum advisers are considering whether to include pupils' own assessment of their progress in annual school reports.
Mr Donald, who has had experience of both the state and independent sectors, said the traditional report card is "retrospective and too late".
Parents needed earlier information in order to give advice.
But parents had to accept that they would get a lot of information and sometimes would hear things that they did not want to know.
New annual progress reports, based on personal learning plans, are at the heart of the Executive's assessment proposals for three to 14-year-olds, currently out for consultation.
Mr Donald also criticised the environment in which most parents and teachers meet, particularly when they sit at opposite sides of a desk. "I had the feeling I was at school myself, and some parents can feel that they are on trial," he said. "The environment can be improved by removing physical barriers."
He accepted that there are difficulties in devising more effective reporting systems, either by hand, by post or electronically but "the system has to be flexible enough to cope with the demands".
The format of parents' meetings is one of the areas being looked at by the "reporting to parents and others" project, run by Learning and Teaching Scotland.
Donna Murray, the project leader, told The TES Scotland: "The issue of parents' meetings is being looked at, especially where the meetings are held in a big hall and there may be issues of privacy. We are also looking at whether the set-up allows for two-way communication or if parents are just turning up to hear what they have read in the report."
Pupil involvement in self-assessment is also being looked at. "We are not referring to the end-of-year report but we are saying that pupils could evaluate and record their own self-assessment and this could be attached to the reports that go to parents. We find that children are very honest and parents find it useful because children have the opportunity to explain issues to them."
The information produced by the 22 schools taking apart in the LTS project will be collated in exemplars and shared with other schools in Scotland.
Pupil self-assessment is an integral part of a triangular approach to a partnership in assessment, which was advocated at the conference by Sheila Wolfendale, of the school of psychology at the University of East London.
Professor Wolfendale suggested that parents would contribute by attending meetings, completing parental profiles and contributing to a home-school diary, among other things; teachers would carry out standard formative and summative assessments, talk to parents and complete reports; and pupils would have a "dialogue" with teachers and parents, complete self-reports and be involved with in-school events such as drama, role play and circle time.
This approach, Professor Wolfendale added, would enable target-setting for school-based learning, encourage reciprocal learning activities at home and give parents a greater understanding of the curriculum.
"It would also help teachers to know more about each child and hisher home circumstances, reassure children that significant adults listen and work together on their behalf, and help the adults to understand the child's views and concerns."