If you are looking for books with a male protagonist, you can read about the adventures of Henry Huggins and his dog, Ribsy. Although these books were written in the 1950s and 60s and are a bit dated with regard to social and economic issues, the characters are timeless and many of the themes and lessons are still relevant today.
Henry Huggins
Henry and Beezus
Henry and Ribsy
Henry and the Paper Route
Henry and the Clubhouse
Ribsy
Another popular series focuses on the lives of Ramona Quimby and her older sister, Beezus. These books span a greater time period with the first being published in 1968 and the last one going to print in 1999.
Beezus and Ramona
Ramona the Pest
Ramona the Brave
Ramona and Her Father
Ramona and Her Mother
Ramona Quimby, Age 8
Ramona Forever
Ramona's World
Newer editions have been given updated illustrations. In my opinion, the original illustrations better capture the era about which Ms. Cleary was writing. If you can, I would recommend trying to find an older edition at your local library.
If you want to learn more about this wonderful author, be sure to read her two-part autobiography: A Girl from Yamhill