Joanna, Alex, Daisy, James, Tom and Crystal, from years 8 and 9, made placards and created a huge banner with declares there is no planet B.
They have gone on strike from school and are spending the day raising awareness of their protest and their wish for action on climate change.
Joanna, 14, said: "Last night we emailed the school to say we would be doing this.
"I wanted to do something - I am very much into the environment
"In the morning we tied the banner onto the bridge near school so people could see what we were doing. We stayed there about an hour then went into the centre of town.
"We put our banner on the Market Cross.
"So many people are saying good for you."
Today’s strike is part of a movement that started in August when the 16-year-old schoolgirl Greta Thunberg held a solo protest outside Sweden’s parliament.
Now, up to 70,000 schoolchildren each week are taking part in 270 towns and cities worldwide.
Joanna and her friends were inspired by Greta to take part in the strike today.
"I thought, there is no reason we can't do this," Joanna said. "I am a passionate vegan. I really care about animal welfare. I would really it if people thought about how they are treating their planet."
Her father Paul Freegard said he totally supported her action: "I am happy for them to take this action. On climate change, I really think adults have failed them."