Throughout the show's run, it has been shown that Bart is almost always more attentive and focused on his complex pranks and hijinks than anything academic related. As it turns out, there's a medical reason as to why Bart is the way he is. During the late nineties, there were dramatic increases in behavioural disorder diagnoses in children and controversy was stirred up over whether or not to medicating these diagnosed children was a good thing. This social context helped inspire the episode 'Brother's Little Helper' in which Bart is diagnosed with attention deficit disorder after many years of causing havoc around Springfield and generally being a nuisance. After being prescribed some experimental drugs to control his ADD, Bart became incredibly smart and studious before slipping into paranoid weirdo mode until he was weaned off the meds by the episode. Despite generally fading into the background ever since, Bart's ADD has come up briefly every now and again, such as in the episode 'Special Edna' where Bart showed that he was more than willing to do advanced algebra just to distract himself from doing his actual homework.