Government data shows 83% of secondary pupils attended the first day back at school in Jersey on Monday.
There were no confirmed Covid-19 cases reported in schools on the day students returned, the government said.
Fewer than five students aged 15-18 years old, out of 1,510 volunteers, tested positive for the virus between 1 and 10 January.
Acting Education Minister Deputy Jeremy Macon said the latest figures were "very encouraging".
Primary schools in Jersey saw 93.6% of pupils return after the Christmas break, with 2.5% of absences attributed to coronavirus.
In secondary schools 4.7% of absences were Covid-related, according to data from the Department of Children, Young People, Education and Skills.
On Monday Senator Tracey Vallois resigned from her role as education minister, claiming her concerns about the reopening of schools had been dismissed.
'Monitor the situation'
A total of 1,912 nursery and school staff, including 1,351 teachers, were tested between 1 and 10 January as part of a voluntary testing programme introduced by the government.
It said fewer than five members of staff had tested positive for Covid in this period.
Speaking on the latest figures, Deputy Macon said: "These show we have had an encouraging start of term for primary students returning to schools yesterday following an extended Christmas school holiday break.
"The secondary school figures are lower, but in part due to one year group off school due to staff shortages and a number of Covid-19-related absences.
"We will continue to work with schools to support them and monitor the situation daily with the Department."
Continued data on school attendance figures and uptake of the testing programme are due to be published daily on the government website.