The Chihuahua Chase — A.E. Cannon

When Teddy Krebs's speedy if homely little dog goes missing right before the town Chihuahua races, fourth-grader Addie May Jones can't resist Teddy's plea for help. Soon she has two mysteries on her hands: Is there a dognapper on the loose? And why won't Teddy stop making a pest of himself? Addie May turns detective to find the vanished pooch and at the same time discovers a bad case of puppy love.

The Chihuahua Chase is a 2011 Bank Street - Best Children's Book of the Year.