First lets discuss the matches of the story in both book and movie Wonder. In the movie they did a great job at making the same personalities of characters as the book. Talking of great jobs the makeup and dress up also past many characteristics of the characters.
Now let's consider the areas where the movie did not follow the book. Although the characteristics where past on the appearance did not, for instance in the movie via had brown hair but originally she had beautiful black hair, and in the movie they mist many important details like Auggui Getting a second dog or him getting hearing aids.
Overall, I thought that the book was better because it is the original and more understandable story.