The group took time off school and stood in the town centre to raise awareness of the issues surrounding climate change. They held signs and placards reading: 'There is no planet B,' 'School strike for climate,' and 'Save our planet.'
Many students across Argyll and Bute, including some of those who participated in last Friday's strike, took part in a similar school walk-out the week before, on Friday September 20.
Sixteen-year-old Tristan Holmes, the main organiser of the CGS pupils' protests, told the Courier that the Global Climate Strike was a week-long event, from September 20 to 27, so they decided to hold protests both at the start and end of the week.
Tristan said they had met with opposition from the school's head teacher, but he added: 'We would argue that it is our individual right to strike. We want to raise awareness - it's not like we're skiving, we're doing it for a good cause.'
He added: 'We're passionate about the climate. We need to raise awareness, not just among children, and call for the government to take action, because we really aren't doing enough. People are already dying from this.'
The pupils said they received lots of support from passers-by, and were even given free hot chocolate - in reusable cups - from nearby café Tea on the Quay.
All the youngsters who spoke to the Courier said they had their parents permission to take part but one later admitted they had not officially told the school about their plan to strike and, as such, could understand Mr Fyfe's concerns.
A spokesperson for Argyll and Bute Council said: 'Pupils who attended the global climate change strike on September 20 were given authorised absence, provided parents informed the school of their absence.
'The following week, however, a group of pupils decided to hold their own, impromptu strike without informing the head teacher. While we are proud to see pupils participating in the global movement to tackle climate change, we have a duty of care and could not support unofficial action where groups of pupils fail to attend school without our prior knowledge and/or permission of parents.'
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