Nancy persuades all of the other girls not to try out for a babysitting job so that she is sure to get it, but soon she and little Lara Johnston find out that they hate each other and Nancy gets the sack, but she is too embarrased to tell the others. Meanwhile Arthur sets up a ""personal"" babysitting service but hires the other kids to do the sitting for him.

Nancy is thrilled to be going to her grandparent's in Miami for summer vacation, but when she arrives she soon finds that things aren't as great as they seem. The other guests are boring, the restauraunt is horrible and no matter what Nancy tries she seems destined to be banned from using the pool. However when Polly arrives at the site she and Nancy manage to work together and have a great time, but as the two arrive back at school Nancy is still determined to stay away from Polly as much as possible.

Jessie is worried about failing the eye-test, but his attempts to cheat end up with him having to wear glasses, making it hard for him to see anything. Meanwhile, Nancy and Charlie are competing to be voted best athlete in the class and Nancy thinks she has worked it so that they will tie, but when Jessie is unable to see the ballot paper he accidentally votes for Charlie, winning him the vote.

The kids all get excited about the chance to see the ""Your Body is Changing"" film, until they learn that they have to go with a parent. Jessie thinks he's got away going without a parent until his mom turns up and manages to totally embarrass him, making him miss most of the movie and not finding out where babies come from. Meanwhile Polly opens up her Spoon Hospital for another year, but tragedy strikes when she accidentally breaks lunchlady Martha's serving spoon.

Nancy and Vinny start going out after they find they like each other while cleaning the classroom, but as Nancy thinks everything is going perfectly she discovers that Vinny is cheating on her with another girl. Meanwhile Arthur learns that his aunt is throwing him a surprise pool party but he doesn't know how to swim and signs up for lessons, only to find out that Polly is the teacher.

As Haloween approaches, all the kids are excited about what costumes they are going to be wearing. Vinny and Jessie both agree not to go as Space Beasts, but both then break their promise, however while Vinny comes in a proper Space Beast costume, Jessie's home-made version makes him look more like a mermaid. Mr Besser is determined to go as a pirate, but when Vinny and Jessie teach his parrot bad words they both get found out at the party. Meanwhile Nancy finds out that Penny is going as Little Bo Peep and decides to buy the same costume, but when she arrives at the party she can't find Penny, only a person dressed up as a sheep. Assuming that it must be Penny, the two enter the costume contest together, only to find out too late that it is actually Polly inside the costume.

All the kids are excited as the school fair approaches and every one of them is determined to get their hands on the two bikes up for grabs. As the stalls get under way, it seems that every kid has their own way to try and mnake the most money, however while the others are concerned with running stalls, Arthur is offering to promote each stall if the other kids pay him and then takes all the custom by offering kids the chance to win a stereo if they can knock down the cans at his stall. As havoc prevails at each stall, the kids are all eager to learn who has won the bikes when they find that the hopeless Mr Jackson has collected up all of the money without counting it first.

After tricking Mr Besser with a dollar tied to a piece of string, Vinnie and Jessie are both sentenced to be his helpers. As well as the horror of doing the principal's duty, Jessie also has a spelling test to look forward to until his mom tells him that he is going to have to stay at his Nana and Pop Pop's because she and his father are going away for a few days. Excited at the prospect of missing the test, things aren't as great as they seem when the house is snowed in and the power blacks out. Jessie tries to make the most of it, but as things start to get better his mom arrives to collect him, bringing with him the spelling test so that he can do it on the way home.

The other kids are all amazed when Jordan's baseball skills suddenly start improving and she explains that it is due to Feng Shui and positive chi. Intrigued by the spiritual lifestyle, Nancy becomes obsessed with Feng Shui and soon Miss Graves is forced to humour her new lifestyle and splits the class in two to see whether Feng Shui really has any benefits. With Nancy and Vinnie heading the two sides, the rest of the kids keep switching their minds as to whether Feng Shui works or not, however Nancy's side seems to be having the more luck. However when the others find that Nancy has a pocket mirror in her bag, they accuse her of trying to steal their chi and turn on her, causing the class to revert back to normal.

All of the girls get excited when they see the new Cleopatra hair-style by Simon of London and in an attempt to become more popular, Nancy tells the others that she is going to get her hair cut by Simon. After begging her mom and promising that she won't ask for anything ever again, Nancy finally manages to get to the hair salon, but the resulting style from Nigel the cleaner makes her look more like a poodle. Meanwhile Polly can't stand it when Freddie gets a better grade than her on a paper on butterflies and insists that Miss Graves remarks them, sparking a debate that eventually leads them to Mr Besser's office.

Shocked by Jessie's consistently poor maths scores, Miss Graves recommends him for the remedial program, but rather than attending the lessons Jessie spends the time bowling and going to the cinema. However when he finds out that his improvement is going to be tested, he bribes Sanjay to take the test for him, but the miraculous increase in his scores ends up with Jessie being moved from remedial maths to advanced maths. Meanwhile Polly sets up a stall selling spoons in school but finds that interest amoungst the other kids is low.

In order to not have to perform Mr Flop-Flop the Christmas Bunny at the school play, the kids band together to force Mr Besser to hand over control to them, however the ensuing arguing ends up with Nancy taking control of the play, much to the annoyance of the others. When the day of the performance arrives, Nancy and the others all end up stealing each others lines and although the play is a hit with the parents it turns out to be rather unconventional.

Miss Graves is called to the doctors when it is believed that she has medical problems until it is revealed that it was just a mix-up, however rather than returning to school she decides to take the rest of the day off. Back at school, Mr Besser is forced to take over as the substitute teacher for the class and soon appoints Polly to take over his duties in order to get rid of her infuriating ways. When Vinnie writes an essay in which he calls Mr Besser a cold hearted liver butcher, he thinks that he is going to end up in permanent detention until he realises that he has misspelt Besser, saving himself from punishment.

As election fever hits the school, everybody seems to be running for class president except for Polly who is off ill. When Nancy is made to go round and see how Polly is, she lets slip about the elections and Polly forces herself well again in order to stand for president, forcing the rest of the competition out of the race and winning by default. However when the kids grow tired of Polly's forceful ways, they lead a revolt to force her out of power.

In an attempt to become one of the popular girls, Nancy befriends one of the girls and quickly becomes part of the clique, much to the annoyance of her classmates. However the other girls soon turn on Nancy, forcing her out of the clique and leaving her with no friends. Meanwhile Jessie's mom tries to be more understanding towards her ""class G"" child, however her attempts to bond with him go horribly wrong when she has to present his class report on airplanes.

Relentless in her attempts to incorporate Lithuanian Studies into the curriculum, Polly insists that the school hold a traditional Gazotski folk dance and after much consideration chooses Sanjay to be her partner. Although Sanjay is initially apprehensive, he quickly becomes infatuated with Polly however she is disgusted by his poor dancing skills. Meanwhile the strain of being a teacher is growing too much for Miss Belanchof until Miss Graves helps her become more organised, until one of Miss Graves' lesson plans wins Miss Belanchof a plaque and a cheque for $5,000.

Determined to get tickets for the Sidewalk Boys concert, Nancy turns to Arthur for help and the two weave a plan to get in by pretending to be members of the press. However once inside the two become worried that they will be found out and both leave before the concert has even started, fearing that they will be found out by the security guards.

Vinnie is horrified when he finds out that Mr Besser has married his Aunt Cookie, especially when the two move in and the kids at school find out. However when Vinnie's aunt finds out that Mr Besser is broke she leaves him and relations between Vinnie and Mr Besser return back to normal. Meanwhile Polly forces Nancy, Jordan, Freddie and Miss Belanchof to attend her Fire Safety School, but when the class is tested by the local fire department it is discovered that Polly's teaching methods are not up to scratch as the class has learnt nothing about fire safety but everything about Lithuania.

The kids are all excited about going to Squirrel Camp until they learn that Miss Belanchof is covering for their normal Squirrel Girl leader. While Penny, Nancy and Polly try for their Wilderness Survival badge, Nancy finds herself face to face with a hungry bear but successfully secures her Bravery badge. Meanwhile Squirrel Boy Arthur is having troubles with his shy kidney and in his attempts to concel his problems ends up having to run the 15 miles to earn his Running badge.

Miss Graves asks Nancy and Polly to perpare reports on the cultures of other kids in the class and while Nancy pairs up with Sanjay, Polly ends up choosing Jordan to do her report. While Polly quickly decides that China has no culture other than that stolen from Lithuania, Nancy is fascinated by Indian culture, especially when she finds out that in a past life she lived in an Indian palace, only to later discover that she lived there as a servant. Meanwhile Melanie Belanchof joins the school in Miss Graves class but pupil and teacher fail to see eye to eye until Melanie is by some stroke of luck transferred into the advanced class.

After Jessie terrorises all of the local babysitters, his mom is forced to look for a new sitter and ends up hiring Polly to look after her baby boy. Jessie begs Polly not to tell the other kids, but when Vinnie sees Polly and Jessie together at home, Jessie lies and says that Polly is his girlfriend. The kids at school start to tease him about it, and Jessie is forced to admit that she is actually his sitter, which only leads to greater humiliation.

Nancy is the best kid in the Gardening Club until she has to go to Miami while her grandma has an eye job to make her look younger. While Nancy finds Miami life more exciting than last time, Jordan and Gabrielle become closer friends and foget to look after Nancy's tomatoes. When Nancy returns, her crops have all shrivelled up and her friends are leaving her out of their conversations, but when neither of them wins the Gardening contest they both start to argue and Nancy takes control again.

Fed up with her daughter's lack of respect, Miss Belanchof grounds Melanie and stops her from going out after school. In an attempt to get out of being grounded, Melanie starts sending herself fake party invitations, but when her mom catches on she is forced to sign up for cheerleading practices.

Nancy is embarrassed to learn that she has asthma and tries to hide it from her classmates, but soon finds that she is worried about every little thing that could cause her problems. She goes to see an alternative doctor, Dr Dedorio, who gives her a supposed miracle cure and Nancy begins to believe that she is getting better until she has an asthma attack during a game of soccer. Deciding to start taking her medication again, Nancy quickly recovers and learns that she isn't the only kid in Room 402 with medical problems.

Jessie signs up for the Student Exchange program, hoping that he will be paired with a smart kid who he can copy off. But when Lars arrives from Outer Maledonia, Jessie realises that the echange isn't all that he hoped it would be when Lars takes over his room and turns out to be just as dumb as Jessie is. However things get even worse when Jessie learns that as part of the exchange he will have to spend time in the frozen wastelands of Outer Maledonia, where the only thing to eat is boiled fish and the sled dogs take an instant dislike to him. Meanwhile, Nancy, Penny and Sanjay sign up for Polly's Spoon School but soon find that they can't take the strain.