The Leaving Cert has been cancelled with students set to get "predictive grades" instead.
Some 61,000 students were due to sit the State exam on July 29.
Education Minister Joe McHugh said: "Unfortunately there is now compelling advice that shows holding the exams and returning to school would be impossible."
Under the revised plans, a system of predictive grades will be given to students in lieu of them sitting physical exams.
Speaking at Government Buildings on Friday, Mr McHugh said Covid-19 has forced the Government to make changes that would have been unthinkable previously.
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