Leigh Botts Series by Beverly Cleary

Leigh has been Boyd Henshaw's number one fan ever since he was in second grade. Now in sixth grade, Leigh lives with his mother and is the new kid in school. He's lonely, troubled by the absence of his father, a cross-country trucker, and angry because a mysterious thief steals from his lunchbag. Then Leigh's teacher assigns a letter-writing project. Naturally Leigh chooses to write to Mr. Henshaw, whose surprising answer changes Leigh's life. (back cover)

Can a stray dog change the life of a teenage boy? It looks as if Strider can. With Strider's help, Leigh Botts finds that the future he hates to be asked about now holds something he never expected: hope.