Nearly 28% of secondary school students in Jersey were absent on the first day of term.
The government says the attendance rate in secondaries on 4 January was 72.2%, while it was 87.2% in primary schools.
540 students started the term learning from home because a total of 231 school staff were absent - half of them teachers.
Education says remote learning is being rotated through classes so 'no-one is unfairly disadvantaged'.
Headteachers have been told to take a compassionate approach to school attendance on a case-by-case basis.
Education says it is responding to the concerns of parents in 'extraordinary circumstances' because of the current wave of Covid-19 infections.
There are currently more than 3,800 known active cases, with 507 positive results returned in the latest 24 hour period.
Students are expected to stay away if they have the virus, but there has been some confusion about whether those living with someone who is infected should attend.
Education bosses say head-teachers have the discretion to authorise absences on compassionate grounds, which would include a parent whose positive being unable to take their child to school.
They say children who need to shield because they are more at risk – or live with someone who is clinically at risk – can provide a letter from a medical practitioner and their absence would be authorised.
But those from Covid-free households and missing from class without reason will be marked as an unauthorised absence.
"With the increase in COVID-19 cases, we know that there are some parents who will feel concerned about the return to school.
As we have done through the pandemic we continue to urge parents to send their children to school, as long as they are asymptomatic and have not tested positive for COVID-19, and do not have any specific medical vulnerability.
Not attending school has an impact on children and young people’s learning, health and well-being at critical developmental stages. The greatest negative impact is on the most vulnerable children. With risk mitigation measures in place, schools are safe environments for children”
If you are concerned about your child’s attendance, you should speak to your school in the first instance" - Seán O’Regan, Group Director of Education.
Students are being asked to take regular home Covid tests, and pupils in secondary school are required to wear masks in the classroom.
"Again, staff and students have come back to school, on the first day of term, ready to adapt again, and I’d like to give them my sincere thanks for their tremendous effort and resilience.
Our schools have faced 22 months of non-stop challenges. Throughout that whole time, staff have shown amazing patience, professionalism, and dedication in continuing to educate children and young people as we navigate through these difficulties.
I’d like to extend my sincere thanks to each and every one of them, and to those who are stepping outside of their usual roles to support students at the start of this term and put children first.” - Deputy Scott Wickenden, Education Minister.