The class 12 students appeared for History exam, while no paper was scheduled for class 10.
"The History exam scheduled for today went off peacefully across India, foreign centres and Delhi, including northeast areas. The centres in northeast Delhi recorded 98.33 per cent attendance today. The absentees included mostly private candidates," a senior board official said.
"The board is making efforts to contact them to extend help, if any required, so that they can resume their exam schedule at the earliest," he said.
The CBSE on Sunday said any further delay may hamper chances of students in securing admission to professional courses like medical and engineering, though it is ready to conduct fresh exams for students who are not able to appear.
The schools are closed in northeast Delhi till March 7.