More than one million 12 to 15-year-olds have now had a COVID vaccine in England.
Jabs for this group began on 20 September and NHS England said more than 3,500 schools had hosted vaccination clinics.
Hundreds more schools will be visited by NHS teams next week.
Consent letters are sent to parents and guardians, with most children getting one dose of the Pfizer/BioNTech vaccine. Some who are more vulnerable are offered two.
Dr Emily Lawson, head of the NHS coronavirus vaccination programme, praised the rapid roll out.
“It is fantastic that one million 12 to 15-year-olds have now had their COVID jabs thanks to the schools programme and the hard work of specialist NHS teams who are either visiting hundreds of schools every single week or our vaccination sites,” she said.
“I would urge families to look at the information together and then book in to give children and their loved ones crucial protection ahead of winter.”
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It comes as experts said they don’t believe the UK will see a “catastrophic winter wave” that will require restrictions over Christmas.
Professor Neil Ferguson, a member of SAGE, said on Saturday that the UK was in “quite a different situation” to some European countries reintroducing measures as their cases increase.
Austria, for example, has announced a 10-day lockdown for anyone who’s not double-jabbed and there were arrests and protests in the Netherlands over a new partial lockdown.
Meanwhile, UK figures on Sunday showed another 36,517 daily cases and 63 COVID-related deaths. That compares with 30,305 cases and 62 deaths this time last week.
The latest seven-day average for cases is 37,488 – a fall from a month before when it was nearly 40,000.
Average deaths stand at 156, compared with 117 a month before.
Meanwhile, another 448,670 people had a booster vaccination on Saturday, taking the total who’ve received a third jab to 12,613,256.