I'll refer you to their website.
However, I am going to mention one group of organizations which should receive your assistance. Not just in Colorado but across America. These are the arts, humanities, and culture groups that entertain and teach millions of folks in thousands of towns and cities.
Here's the thing -- there's more to creativity than just writing. There, I said it! I'll wait a moment until you get off the floor. In fact, much of what goes on in arts & humanities begets authors, and vice-versa. For instance, an author may have a fantastic story or manuscript turned into a play. Or, perhaps, a director loves a book so much he or she turns it into a movie. Conversely, a painting, sculpture, or a song may inspire a writer to transform it into a story. It's the Circle of Life, minus that whole eating each other thing.
To put it another way, creativity is an intricate and interconnecting web of artists, musicians, actors, playwrights, librarians, and, yes, authors. To make sure these folks reach their pinnacles through teaching and participation, an intricate and interconnecting web of donations to the organizations which help them is needed. And, like in the Circle of Life, it comes back to you.
So, tomorrow, please help those arts, culture, and humanities organizations in Colorado which assist current and new creatives to excel. And for those who don't live in Colorado, donate anyway, even if your local group says they aren't accepting donations right now. Trust me, they'll be happy for whatever you can provide.
You can find the list of Arts, Culture, and Humanities organizations accepting donations via Colorado Gives Day at this site.