Hi Tamara, 
Thank you for using Ask Extension.

You are posing an interesting question.  I'm not sure what you mean by 'coloful'.  Shady areas present a challenge because nearly every plant that flowers (for color) will do better with at least partial sun.

Many rhododendrons will do fine in shady areas, with flowers in the spring, many are evergreen, with interesting leaf forms.  Evergreen azaleas can also do well.

For natives, I like evergreen huckleberry Vaccinium ovatum It's new growth is reddish bronze but hardens to dark green.

Oregon Grape is another alternative that will do okay in shade.

Some varieties of berberis (barberry) might work but could get leggy in shade.  

It may be worthwhile to go to your favorite nursery and see what they have in stock and other recommendations.