Order: FALCONIFORMES - Kites, Hawks, Eagles, and Allies
Family: ACCIPITRIDAE - Hawks

Cooper's and Sharp-shinned are very difficult to tell apart. Here is a link that may help.
http://www.birds.cornell.edu/pfw/AboutBirdsandFeeding/accipiterphoto.htm
Sharp-shinned Hawk - Accipiter striatusSharp-shinned Hawk - Accipiter striatusSharp-shinned Hawk - Accipiter striatusSharp-shinned Hawk - Accipiter striatusSharp-shinned Hawk - Accipiter striatusSharp-shinned Hawk - Accipiter striatus