CM with World History

I am new to CM style, but love the idea. It’s easy enough to implement with the younger children, but am having a hard time with my 9th grader – especially in the area of World History.  Colleges want that World History requirement checked off.  What does this look like in CM style?  Do I just let her pick a few random things that interest her and let her only learn about Phonecian hyroglyphs and the various Egyptian empires?  Is that enough? It doesn’t seem well rounded enough, but I don’t think she should have to complete the entire text book either…