Schools in Singapore, from primary to junior college levels, experienced no drop in attendance as they reopened last Tuesday.

Average attendance for the week was about 97 per cent among students who were rostered to return, which the Education Ministry said is "similar to the pre-Covid-19 rate".

Still, it was not business as usual, with several teething issues involving the measures to stem any spread of the coronavirus.

Students were not used to wearing masks for a prolonged period of time, the Ministry of Education's (MOE) director of schools Liew Wei Li told The Sunday Times.

Teachers had to get used to using face shields or masks when in class, and juggle between face-to-face classes and teaching students at home virtually.

Schools also had to manage congestion at entry points during arrival and dismissal times.

Since the circuit breaker was eased on Tuesday, graduating cohorts of Primary 6 and Secondary 4 and 5 have to go to school.

The rest will rotate weekly: learning in school one week and learning at home the next. Those in Primary 4 and 5, and in lower secondary returned last week.

Ms Liew said schools have set aside time to familiarise students with the new routines and safety measures, such as keeping a safe distance during playtime.

"The weekly rotation schedule... gives schools the opportunity to adjust, take in feedback from parents and students, and find new ways to ease students into the arrangements," she added.

Up to 50 per cent of students in junior colleges and the Millennia Institute also returned, with priority given to graduating students.

At the pre-school level, Kindergarten 1 and 2 children were allowed to resume classes. Those in Nursery 1 and 2 may go back from tomorrow.

The Ministry of Social and Family Development (MSF) has observed - from visits to pre-schools - that children were able to adhere to the new rules. Most kept their masks on through the day, removing them only during meal and nap times. They washed their hands correctly and frequently and keep a safe distance from their friends, a spokesman said.

Pre-school operators The Sunday Times spoke to said reopening centres by age group is helping children settle into their new routines.

At PAP Community Foundation (PCF) Sparkletots, about 90 per cent of Kindergarten 1 and 2 kids had returned since Tuesday.

Ms Marini Khamis, senior director of PCF's pre-school management division, said children tend to "be more open to following practices such as wearing a mask when they see their teachers and friends doing the same".

Ms Thian Ai Ling, general manager of NTUC First Campus' My First Skool, said the average attendance across centres was about 85 per cent for Kindergarten 1 and 2 children in the past week.

To help children ease back into routines, an online class was conducted last Monday, where they could talk to their teachers and friends, and be guided on how to wear masks.

"At times, some children could get excited and (get) a little closer to their friends in school... We will continue to reinforce safe practices in children, and engage the parents and partner them in keeping our children and pre-school environment safe," Ms Thian added.

Parents welcomed the return of school and said the transition was manageable.

Mr Abdillah Hashim, 41, who works in an engineering consulting firm, has a daughter and son in kindergarten and nursery at the same centre.

His son was allowed to go back on Tuesday as he is enrolled in an early intervention programme.

Mr Abdillah said: "The teacher informed me that my kids did not have issues wearing the face mask for the whole day. But my daughter said they have to eat alone now, instead of sitting with their friends."