But today (Friday 5 November), the Swedish climate activist has led the Fridays For Future movement she founded through the streets of Glasgow.
The protest has tied in with today’s theme for the conference, with delegates looking at education of both young people and the wider public.
So when did the protest get underway - and what’s it about?
Here’s what you need to know.
When and where will Greta Thunberg’s protest take place?
The Fridays for Future march got underway in Glasgow’s Kelvingrove Park at 11am.
It passed within shouting distance of the COP26 Green Zone at the Scottish Event Campus (SEC) before winding up in George Square at 1pm.
Between 1pm and 3.30pm, marchers have been hearing speeches from prominent climate youth activists, including Ms Thunberg and Vanessa Nakate, as well as local trade unionists.
The organisers told NationalWorld 25,000 people are expected to join today’s march, with tens of thousands taking part in other marches across the UK.
PA said the number of people attending the Glasgow march was around 8,000.
Many of the protesters are expected to be of school age.
What will Greta Thunberg say at Glasgow protest?
It is not known exactly what Greta Thunberg will say at the protest.
However, her speech is expected to tie in with today’s education theme at COP26 and will likely reflect on how much progress the conference has made so far.
In general, today’s protesters want to get across the urgency of the climate crisis to the politicians and other delegates who are attending the summit.
Speaking to BBC Radio Scotland’s Good Morning Scotland programme on Friday one activist said the young protesters are convening because they “do not have a choice”.
Evelyn Acham, a Ugandan activist with the Rise Up movement in Africa who will be attending today’s protest, said.
“So many young people have given up school to become full-time activists, some have given up work, some have given up going for a masters degree, just because they’re seeing the urgency of this,” she said.
“To the young people, this is very urgent, because we need to settle down and do other things, we need to go back to school, we need to focus on the future.”
Ms Acham added that “the young people going out there to march gives us hope”.
“The future belongs to those young people, because they still have a lot of time, they haven’t achieved a lot, but the older generation have already achieved so much and (climate change) probably won’t be so much their problem.
“But young people still have work to do, they still have school to do, they have a future to build, so this is our concern.”
What has the Government said about the march?
The Prime Minister Boris Johnson’s spokesperson said young people missing school to attend the Glasgow demonstration and others around the country was “extremely disruptive at a time when the pandemic has already had a huge impact on their learning”.
Speaking on Times Radio of Friday morning, Education Secretary Nadhim Zahawi said he thought school age climate protesters should only demonstrate at weekends rather than during school hours.
“I have to say, I wish they were doing it on a Saturday and a Sunday, not in school time,” Mr Zahawi said.
“I’d hate to get into a situation where headteachers and teachers are having to fine families and students.
“We’ve got two weekends of COP here in Glasgow when they can have lawful demonstrations, and they should have those and have the right to do that, and I would happily engage with anyone who wants to come and tell me exactly what they think.”
While COP26 spans two weekends, Sunday 31 October was not an active day of talks and Sunday 7 November is a ‘rest day’ for the delegates.
It would therefore only leave youth protesters with one day in which they could protest, if they were to follow Mr Zahawi’s advice.
The COP26 conference draws to a close on Friday 12 November.
It comes as Nadhim Zahawi is set to launch a new sustainability and climate change strategy at COP26 today that will “embed climate change evidence” into curriculums.
Additional reporting by PA
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