How to Crowdsource Content?

What I am undertaking is not terribly far removed from writing an encyclopedia alone.

And while I am a decent writer, I just can't see spending the next year or more writing all this content along with all the other hats I wear.

I am trying to find some way to crowdsource this content for a curriculum where I can become more of the editor but I am not making much progress figuring this out.

Any ideas welcome. Thanks in advance.