In the very beginning of the film Erasmus talking to 'producer' Paul as the camera pans back and forth; in one in back of Paul he wears his sunglasses, but not in the rest of the shots.
The credits have an extra-special 'thank you' to EJ Martinez Elementary School; but most, if not all, of the school scenes were filmed Wood-Gormley Elementary School--the sign can be seen in several outside shots of the school entrance.