The head teacher at Holyrood Secondary in Glasgow, Sharon Watson, says it has been a "challenging" time for staff, pupils and parents.
She told the BBC that staff used "everything they knew" about their pupils to help decide their grades.
Ms Watson was watching some of her pupils as they were sent their results by text message.
"It's really great to be here," she said. "You can’t not, as head teacher, be really excited and really proud of all the young people that are here, but also all the young people that are at home, and opening their results just now.
"So well done to all of you from me. You deserve it, you’ve done everything you should have."