Officials in Maryland's second-largest public school system blamed computer glitches for grade and credit errors on thousands of students' report cards in February.
"We do have a lot of worried parents and students," said Brian Porter, representative for the Montgomery County Public Schools.
The school system has about 129,000 students. Problems affected 66,288 report cards produced for secondary students.
Officials said grading or credit errors affected about 3 percent of the report cards, while 15 percent of the report cards contained formatting errors.
"It reflects lingering problems with a new student information system we began using...