Red Birds - Robins, Cardinals, House Finches
Robin (Spring Splendor)
Blue Birds - Jays and Bluebirds
Yellow Birds - Goldfinches and Meadowlarks
Hummingbirds - Flight
Hummingbirds - Summer Sizzle
Brown Birds - House Sparrows, House Wrens, and mourning Doves
Black Birds - Crow, Red-Winged Blackbird, Starling, and Cowbird
Black and White Birds - Woodpecker, Chickadee, Nuthatch, Towhee
Gray Birds - Pigeon and Mockingbird
Owls (Summer Series)
Geese (Autumn 2010)
Winter Bird Study (Migration)
Winter Wednesday Birds
Spring Bird Study (songs)
Woodpeckers
Here are specific challenges from the Handbook of Nature Study for different bird topics if you are interested in learning more:
Wing and Tail Shape