If you're interested in contributing to the existing curriculum, the repository is on GitHub at github.com/mechanicalgirl/young-coders-tutorial. Pull requests with changes to the curriculum are always welcome, but may not necessarily be incorporated.
What we need currently:
Unfortunately, we're not set up to take donations yet. For now, the best way you can help financially is to contribute to the Python Software Foundation. Your donations to the PSF will help to finance lots of wonderful programs and classes for Python students around the world.
You can also sign up below for the Let's Learn Python mailing list to keep up to date on what's going on with the site and learn about all the new developments on the way!