The scene opens on Strepsiades and his son, Pheidippides, in bed. Strepsiades is unable to sleep because of anxiety over his debts accrued for the sake of his son's aristocratic hobby of horse-sports. In his anguish, Strepsiades recounts how he married into aristocratic blood and has been paying for it ever since. But he arrives upon a plan to escape his debts, and wakes Pheidippides to tell him his plan of enrolling the youth next door in Socrates' Thinkery, where he will learn the skills of dishonest forensic discourse. Pheidippides refuses to become associated with the untanned and blasphemous students of Sophistry and threatens to leave for his uncle's house.
Strepsiades decides to enroll himself. He goes banging on the Thinkery's door, which is answered by a student. After the student tells him some of the wonderful ideas that were birthed (and almost birthed) inside, Strepsiades demands in for an education. The student allows him through the doors, and he observes students studying geology, astronomy, and cartography. He then spies Socrates, suspended in a basket above the stage. He begs to learn the Sophist's art. Socrates agrees to take him as a student, and initiates him into the Thinkery with pseudo-religious pomp. The new student is introduced to the Clouds, who are divinities. After some jokes, he and Socrates retire to the Thinkery.
The parabasis, rewritten in the extant revision of the play, reprimands the audience for not selecting The Clouds as the winning play of the festival in which it was presented. Aristophanes professes it to have been his best work, and recounts its merits as compared to the slapstick tomfoolery of the other comic poets. Granted, he violates all of the prohibitions he recommends (on beatings with sticks, the use of leather phalloi, the superfluity of stock attacks on Athens' prominent citizens) in this very play...
The parabasis is followed by an ode by the chorus which, in contrast to earlier statements concerning the ontological status of the Olympians, praises them and invites them into the dance (are we here supposed to get an inkling of their true nature as revealed at the end of the play?). The chorus next relates the frustration of the Moon at Athens' disregard for her; they created a calendar which was not lunar (and, justly, confusion followed).
Socrates emerges complaining about Strepsiades' inability to learn. He calls on Strepsiades, tries to teach him a thing or two about grammar (a ridiculous thing or two, but a thing or two nonetheless). This unsuccessful, Socrates persuades him to lie on the couch and meditate on beating his creditors in court. Strepsiades is slow at first, being eaten alive by bedbugs; yet he manages to invent a few fanciful solutions to his dilemma. The last is so preposterous (hanging himself) that Socrates gives up and kicks him out of the Thinkery.
Still in a financial bind, Strepsiades, upon the counsel of the chorus, decides to send his son to learn from Socrates. After a ridiculous display of the things he has learned there, Strepsiades finally gets his dutiful son to begrudgingly accept tutelege at the Thinkery.
Socrates accepts the new student, and states that Right and Wrong (or, as in Arrowsmith's translation, Philosophy and Sophistry) will instruct him personally. Right and Wrong enter and begin debating to determine the best of the two. Wrong wins. Pheidippides is left at the Thinkery to be taght.
Strepsiades returns for his son on the dueday of his debts. Pheidippides manages to conjure up an argument which will absolve all his father's debts. Two of the debtors comes knocking; Strepsiades belligerently sends each away (chasing both with a stick). He and his son retire to the house.
They emerge again after Pheidippides has physically beaten his father. He defends his actions with his new argumentative skills to his father's dismay and satisfaction. Yet when he claims to be able to defend beating his mother as well, Strepsiades runs mad with rage and burns down the Thinkery.