Great intent to help kids learn to code, good project! But I do think the landing page needs a bit more meat and a better onboarding. Not all 12 year olds or their parents know what GitHub is and might get confused by it. Maybe add some more explanation on the page what they can expect and maybe need to have some instructions around how to set up GitHub and what it is
I think if this is targeted at kids, you may want an email signup. I.E. someone just getting started with coding probably doesn't have a Github. That said, I love the initiative to help kids/people learn to code!
this is cool, but do kids need to download the files to work on? coding inside the platform would be a hit