If ds were still at school, I'd have been impressed if he wanted to do this (and would've been ok with him participating). 
As it is, he turned 18 in September and is in 1st year at Uni. He is also very angry about the lack of urgency about dealing with climate change, so I know he'd have been interested with this protest. He reads a lot around the subject (even though it's not the subject that he's studying).
I was impressed with the reporting of all these engaged young people who care about the future. Must have been scary for politicians though, who rely on uninformed, unengaged voters who will vote for whichever politician is the "correct" colour for their power 