Primary and secondary schools here resumed classes yesterday, after an unprecedented closure last Friday due to worsening haze.
Schools across Singapore have since put precautionary measures in place should the air quality deteriorate further.
At least 10 schools The Straits Times spoke to have moved some classes to air-conditioned classrooms, while a few may consider rescheduling their year-end exams.
For most of the school day yesterday, the 24-hour Pollutant Standards Index (PSI) stayed within the unhealthy range of 101 to 200.
The National Environment Agency forecast the 24-hour PSI to be in the very unhealthy range of 201 to 300 today.
Mr Lim Jit Hin, vice-principal of Park View Primary School, said the school has plans to move its Primary 6 classes to air-conditioned classrooms. Pupils in these classes will be sitting the written papers for the Primary School Leaving Examination from Thursday.
"We do not want the haze to affect them, so we are giving them this support," Mr Lim explained.
He added that the school in Pasir Ris will reallocate some classrooms to ensure it can still hold its year-end exams even if the hazy conditions persist.
Schools here are equipped with air purifiers, and sufficient enclosed spaces have also been set aside for the students.
Most institutions have minimised their outdoor activities and moved physical education lessons indoors. Teachers have been asked to keep a lookout for students who are unwell, in particular those with pre-existing heart or lung conditions.
"Students who are unwell will be taken to air-conditioned classrooms," said Mrs Ruby Khoo, principal of Jurong Secondary School.
She added that the school may tap technology to conduct its classes if air quality worsens.
"Our school is prepared to do live streaming of lessons," she said.
"While lessons will proceed in the respective classrooms, students with pre-existing respiratory conditions will be taken to air-conditioned rooms and they will view the lessons from there."
On Sunday, the Education Ministry gave the assurance that schools have haze management plans in place.
School-based student care centres, which offer after-school care services in primary schools, have also tweaked their programmes slightly owing to the haze.
Ms Susan Thng, centre supervisor of the student care facility at Xishan Primary School, said the centre has since stopped its outdoor activities. Previously, pupils were able to engage in outdoor sports, such as basketball, in the later part of the afternoon.
Adding that the pupils now occupy their time with indoor activities such as playing board games, she said: "We should not put our children's health at risk."
If the school shuts again as a result of the haze, her care centre has made preparations to open from 7.30am to 6.30pm to supervise pupils whose parents are unable to make alternative arrangements. Ms Thng explained: "We do not mind a little inconvenience as long as our children are safe and their health is not compromised."