In a worldwide school event organised by the BBC, children are saying what matters to them.
Hundreds of schools around the world are taking part including the world's biggest school in India - with 42,000 pupils!
Set up by the BBC's World Class website, the event helps different schools to learn about each other.
Watch our video of children in Ghana.
We want to know what you think. Have you felt so strongly about something, you did something about it? What things really matter to you?
If you send us a comment, it may be published on the Newsround website, and some comments may be used in our TV bulletins. We'll use your first name and your home town to show that it's your comment; your personal details won't be used for anything else.