Title: Mr. Popper's Penguins
Author: Richard and Florence Atwater
This is a great chapter book to use as an early read-aloud book. I read this to my oldest when he was about 4 and a half and he loved it. In fact, I think it was the first read aloud chapter book we did, and he was eager each day for the next chapter.
It is a fun little story about a man who longs for adventure and ends up with a group of penguins as pets. That ends up to be quite an adventure for him.