We've been staying home for so long, it is nice to play here and meet my friends again," said nine-year-old Muskan Bajracharya.
In senior classes, students were encouraged to talk about the quake or share stories about what happened to their families.
"We are not holding any formal classes and have trained the teachers to help the children overcome the trauma of the quake and adjust to (being back at) school," said principal Govinda Poudel.
The 7.8-magnitude quake damaged nearly 8,000 schools, while some 90 per cent of them are estimated to be have been destroyed in the worst-hit rural districts of Gorkha, Sindhupalchowk and Nuwakot.
The quake struck on a Saturday afternoon when schools were closed. Many had been preparing to open the following week for the new semester.
"I don't even want to imagine what would have happened if it was a school day," said Sakuntala Bhlon, 37, whose two children study in classes five and eight.
The reopening had been declared for May 17, but was delayed after a second major 7.4-magnitude quake rattled the country on May 12.