Formula For Disaster is the fifth episode of Season 7.
At Dimmsdale Elementary School, Mr. Crocker pulls down a screen at the head of his class and a projector reveals his "F Tracker". Timmy Turner has gotten his 5,000th F. Everyone in the classroom but Timmy erupts into celebration. Crocker asks Trixie Tang to tell Timmy what he's won, and like a game show hostess she reveals that Timmy has "won" an all-expense paid day at Crocker's Military Academy for one. Mr. Crocker shows the camp and it's purpose on the projector screen. The movie shows Mr. Crocker's running a grueling obstacle course early in the morning, and then fighting a bear. Timmy asks how military school is supposed to help his grades. Crocker says to Timmy "don't sass me soldier" and whispers to himself that its all just a ruse to capture Timmy alone with his fairies, which Timmy clearly overhears. Mr. Crocker tells Timmy all he needs to do is have a permission slip signed, Timmy says that his parents would never send him to military school.
However, back at Timmy's house, Mr. & Mrs. Turner are jumping up and down on a trampoline in excitement because they want their son to go to military school to become more mature and improve his grades. Timmy tries to toss all the pencils out of the window but his parents grab an emergency one out of a breakable glass box. Timmy runs up to his room for help from his fairies, only to find that it has become a battlefield. Wanda explains that she and Cosmo are trying to get Poof to take his nap, but he won't do it--now he's turned into a sleep deprived battle plane, and started shooting push pins all over the room. Wanda is brewing up a magical formula, she mixes boring elevator music, a book on the Dewey decimal system, and a six hour documentary on yarn, to create a formula that could put anybody to sleep. Meanwhile downstairs Mr. Crocker has arrived (he is dressed in a military uniform he made up) and has Timmy's parents sign the permission slip. Timmy sees this and runs back to his room for help, but Poof has transformed into a robot creature and is wreaking havoc in Timmy's room. Wanda tries to give Poof the bottle of formula but he slaps it away.
The sleeping formula flies out of Timmy's room and spills its contents into glasses of lemonade Timmy's parents were about to drink, celebrating their "little boy" going to military school. They drink the lemonade and immediately fall asleep. Timmy sees this and wishes that his parents would wake up and change their minds about the permission slip, but before Cosmo and Wanda can grant the wish, Poof steals their wands. Wanda is then captured by Poof, still in robot form, so Timmy is forced to take Cosmo with him for help. Timmy shows Cosmo what happened to his parents, and Cosmo suggest that they use them as puppets to trick Crocker into giving back the permission slip. Timmy says its better than his original idea of just locking Mr. Crocker in the basement forever. Timmy and Cosmo paint over Mr. and Mrs. Turner's eyes so they appear open, and then tie them to strings and use them as string puppets. Timmy's parents are sprawled on the couch while Cosmo and Timmy manipulate them from above on the second floor balcony. Mr. Crocker comes out of the bathroom and tells Timmy's parents they'd better light a scented candle in there. Timmy manipulates his dad and talks through ventriloquism, telling Mr. Crocker they've changed their minds and want the permission slip back. Mr. Crocker says that the permission slip is already signed and its too late, so Timmy and Cosmo use the puppet parents to beat up Mr. Crocker.
Neither Cosmo or Timmy can show themselves to Mr. Crocker without ruining the plan, so they have to find another way to get the permission slip. They speak through Mr. and Mrs. Turner, inviting Mr. Crocker into the kitchen where they rough him up some more while trying to serve him dinner. Somewhere atop a skyscraper, Poof has become a purple version of King Kong, Wanda flies around him in a pink bi-plane shooting formula bottles at him. Back at Timmy's house, the puppets continue to harm Crocker, including Mrs. Turner spilling hot baby corn on his pants. Mr. Turner removes Crocker's pants to be put into the drying machine, but Mr. Crocker had another pair underneath. He takes the permission slip back from Mr. Turner and gives him a burlap sack to put Timmy in, before attempting to leave. Mr. Turner slams in front of the door to block Crocker's exit, grabs him and begins to tango. Wanda appears next to Timmy and Cosmo and tells them she needs their help handling Poof. However, they cannot leave without Crocker figuring out Mr. and Mrs. Turner are really asleep, so Wanda takes the puppets and manipulates them into asking Mr. Crocker to tell them all about himself. Wanda says "That will keep him busy" and brings Timmy and Cosmo with her to get Poof under control.
Timmy, Cosmo, and Wanda run back into Timmy's room, which has become so huge that it now houses all of Tokyo. A three headed purple monster rampages through the city, breathing fire all over the place. Timmy asks why Poof has gotten so big, and Wanda says that if Poof doesn't take a nap soon he will turn into bigger monsters until he explodes. Timmy drives with his fairies in a vehicle holding a large baby bottle with the sleeping formula inside. The bottle is fired inside the middle head's mouth and Poof transforms back to normal and falls asleep. Wanda catches Poof, and a Japanese kid thanks Timmy for saving their city which mysteriously appeared inside his bedroom. Timmy rushes back to the living room where he returns to see Mr. Crocker finishing a long story about his life to the Turners, and then vowing to start a new life as a ninja ballerina cat burglar. Crocker says he doesn't need a military academy to capture Timmy fairies, rips up Timmy's permission slip, and then grabs the left over lemonade glass and drinks from it, causing him to fall asleep. Timmy strings Mr. Crocker up as a puppet just as his own parents wake up. Mr. and Mrs. Turner wonder why the permission slip has been ripped up. Timmy uses Crocker as a puppet to tell his parents that he is a good kid that they should let him play lots of video games. Then Mr. and Mrs. Turner see the left over lemonade as Mr. Crocker is leaving and drink from it, falling asleep again. Timmy and his fairies take Mr. Crocker and toss him into a bus, although Crocker misses the door and his head gets stuck in the closing bus door. Crocker is then dragged to Cincinnati, where he has been banned from since 1985.