A monster-like robot is accidentally released into the hotel, due to the twins. A Halloween party is thrown by London. A typical prank.

Tony Hawk checks into the Tipton; Maddie and London has a crush on their fencing instructor. While Zack and Cody are doing their science project, the problem is that Cody has a fear of germs, and when Zack makes a mistake when analyzing a germ from the kitchen and thinks it's a toxic type of black mold, the rumor spreads through the hotel and everyone starts panicking. Cody gets over his fear after he realizes that he can't go skateboarding with Tony Hawk wearing an anti-germs suit.

Cody is inspired by a guest speaker and tries to do the same with his friends - to hilarious results. Meanwhile London and Maddie compete savagely in the fashion shootout of the year to get on the cover of Teen Trends.

Mr. Moseby gets worried when his older brother Spencer arrives at the Tipton for a visit. Zack and Cody buy a bike, but they have to share it. Maddie and Esteban mess with London's horoscope.

Zack and Cody try to make friends at school. When word gets out that they live at the Tipton, all of the cool kids hang out with them. In the end, the twins find out who there real friends really are. Meanwhile, Carey is practicing dance moves, while London teaches Maddie how to ask Lance out and Maddie tutors London in Math.

Jesse McCartney checks into the Tipton Hotel and Maddie, London, and Zack break into Jesse's room. Zack collects discarded items belonging to Jesse, so he could sell them. Cody enters a science fair, and receives help from Arwin.

A girl at school likes Cody, but after he hires Zack to help, she falls for Zack instead. London's dog Ivana and Maddie's dog Scamp fall in love.

A twins convention is being held at the Tipton Hotel. Zack ends up creating a double date with twin sisters, for him and Cody. London and Maddie end up enjoying a evening with twin brothers.

Zack and Cody join the Wilderness Scouts with their leader being Mr. Moseby. Cody becomes jealous when Zack turns out to be a better outdoorsman. Meanwhile, London claims that Maddie stole her former boyfriend and both plead Carey for advise on her "relaxing" day.

Zack & Cody are cast in a TV show based on the Tipton - "How Suite It Is". Maddie and London sneak onto a Old West movie set in an attempt to meet heartthrob Johnny Vaine.

Zack and Cody wish for superhero powers when they see a shooting star. Their wish comes true and they learn that Mr. Moseby is their villain, who wants to turn all kids into miniature adults.

A competing minimart issues a competition to see who can bag items faster, Zack and Cody accept the challenge. Meanwhile, Mr. Moseby's niece Nia is goofing off with London.

Zack and Cody befriend Travis, a kid whom they rope into helping them impress their dates. They then bail on Travis and go out with their dates, but lets Travis go with the girls instead. Maddie finds a stranger's phone whom she thinks is her crush (because she and the stranger have many of the same interests, which she found out on the lost phone). At the end, the owner of the phone was an old man, but Maddie takes an interest in the old man's grandson.

Zack and Cody have two pet rats as a science project. Mr. Moseby gives the twins tickets to a Red Sox's game to get them away from the hotel. Then a hotel inspector seizes control of the Tipton, because of Zack's mistake. London has a dog party for Ivana and Maddie has to plan.

After getting bad grades on his report card, Zack decides that he needs a way to get good grades without having to study. When Bob, a boy with Dyslexia, shows up in his class, Zack decides that he can pretend to have dyslexia so he can have more time on both tests and reading. Meanwhile, London beats Maddie at chess, and soon Maddie becomes obsessed at beating London at chess.

Prince Sanjei comes to the Tipton to be crown king, but when he tells Zack and Cody he wants to try being a regular kid, Cody poses as him, and Zack takes Sanjei to the mall. Meanwhile, London thinks she saw a UFO, so she invites Maddie over to stay up and look for one. Maddie though, is in it just for the free food and service.

Zack and Cody fall for a French girl who can't speak English very well. Meanwhile, somebody steals London's purse and Esteban tries to help.

Cody runs for class president; Zack decides to run as well, but for the wrong reason. Mr. Moseby gets annoyed with one of the staff members.

Zack borrows money from a guest named Maynard to play video games, but starts to fear him when he can't pay it back. Cody enters a spelling bee. London and Maddie help a homeless family.

Zack makes a new rich friend, who is mean to Cody and thinks he is a dork. Maddie and London have to do a parenting project for school as partners.

It's International Day at Zack and Cody's school and Zack decides to ask a guest named Kumiko, a Japanese opera singer, to be his project. After Zack loses Kumiko, Carey and the boys must fill in as Japanese singers for a convention being held at the Tipton. Meanwhile, Maddie and London get trapped in London's closet.

When a hawk comes and lays her egg Arwin scares it away and somebody has to take care of it. Cody agrees, and he does a good job at parenting. Maddie tries to protest about getting rid of the bird.

The twins compete on a game show in which Cody does the mental challenges, while Zack has to do the physical challenges. Maddie mistakenly sends Mr. Moseby an angry e-mail which she tries to retrieve.

Cody is currently with Barbara, but during orchestra class, Russian violinist Sergei joins as a guest student and starts flirting with Barbara. One of the classmates starts a rumor that Barbara and Sergei are moving back to Russia and are going to sell llamas, making Cody extremely jealous.

Maddie, Cody and Zack compete to get the best guest for London's online chat show. Luckily, The Cheetah Girls and Chris Brown are staying at the Tipton, but who will end up winning the competition?