About Greg Hall Greg Hall lives in Oakville, ON. Books by Greg Hall How Baseball Works by (author) Keltie Thomas illustrated by Greg Hall Ages 8 to 12 Grades 3 to 6 How Hockey Works by (author) Keltie Thomas illustrated by Greg Hall Ages 8 to 12 Grades 4 to 7 How Basketball Works by (author) Keltie Thomas illustrated by Greg Hall Ages 8 to 12 Grades 3 to 6