This is the cover of Derrick the Dentist and the Dangerous Giant, a picture book which was published by JLS Storybook Project for the Korean school market in 2013.
JLS (Jeongsang Language School) has been providing English language learning programs to young Korean students through a reading based curriculum since 1986.
Students learn English as an additional language through contexts presented in fiction and non-fiction reading materials. Classes typically have reading tasks followed by extension exercises that help to develop the students’ skills in listening, speaking, and writing.
Here's a two page spread from the book, showing the wonderful artwork.