I.Q.

I.Q. is a student of the Glenbrook Academy in Mr. Pryce-Jones's 3rd grade class. He won against Brain in a trivia game because Brain gave an answer from modern knowledge, instead of what people thought was correct in the Middle Ages.

Physical appearance
I.Q. is a dog with a cream complexion. His eyes are always half-closed. He also has several hairs in the same design as the Brain's hair. He wears the Glenbrook uniform with a white collared shirt, a dark blue tie, light blue V-neck shirt, and a medium blue jacket bearing the Glenbrook insignia.

Trivia

 * Brain called himself 'IQ' in their homemade movie in "Arthur Makes a Movie"