I Need Some Ideas For Signs

I’m taking the day off work in a couple of weeks to attend a climate strike in the city, and I need some ideas for signs. It’s mostly school kids who are leading the charge on this one (it's primarily a school strike) but they want adults to come and support them and strike with them, so I’m gonna go. I have at least 4 sheets of cardboard I’m gonna turn into signs, so help me out with some slogans? I’m open to ones that:

focus on the future we’re leaving our kids
verbalize support for the students who are striking
slag off the absolute trash government bodies we have who are nosediving us into the ground
environmentally-focused ones
witty and clever ones
snappy, biting ones that offend miners/politicians/corporations/etc
poems
pretty much anything, really