Secondary school pupils and college students in parts of north-west England will continue wearing masks because of concerns about the Covid-19 Indian variant.
Pupils and students across Lancashire are being advised to use face coverings until 21 June. Bolton and Bury councils have also said masks will remain.
The advice comes following a surge in coronavirus cases across the region.
Elsewhere masks will no longer be required in classrooms from Monday.
In a coronavirus briefing, Prime Minister Boris Johnson said the variant could pose “serious disruption” to lockdown easing in England on 21 June, but added that he did not believe that the “present evidence” showed a need to delay the next stage in the easing of lockdown in England on Monday.