Mary-Kate and Ashley are fed up with having a babysitter, especially if it's their elderly neighbor, Mrs. Baker. But when they meet Carrie - one of Kevin's students - they are determined to convince him to hire her. So they devise a plan to get their elderly neighbors, Mr. Fillmore and Mrs. Baker, interested in each other. That way, Mrs. Baker will no longer be able to babysit. But Kevin has his doubts about hiring Carrie and thinks that it's more practical to have Mrs. Baker babysit Mary-Kate and Ashley.
Ashley becomes jealous when, during a slumber party, Mary-Kate reveals that she has kissed a boy. Also, after Paul finds out that Carrie spent the night at Kevin's house, he assumes their relationship is more than it actually is which leads to rumors about a more personal "teacher-student relationship".
Note: Although this episode aired prior to "First Crush", the events of that episode came before "Prelude to a Kiss". Ashley admits to having a crush on Taylor, even though he wasn't hired until "The Tutor".
Kevin hires a math tutor for Mary-Kate. Ashley convinces Mary-Kate to switch places, so that she can flirt with the cute teenage tutor and she can focus on Basketball. But their scheme doesn't go as planned. Meanwhile, Carrie convinces Kevin to ask out a woman at a coffee shop.
Ashley gets assigned Pokey Valentine, her crush, as her partner for a history project. After learning that he is spending time with Mary-Kate, Ashley is furious. The twins set up a trap to catch the alleged two-timer with surprising results.
"Breaking Them Up is Hard to Do"
Mary-Kate and Ashley become worried about losing Carrie when their father, Kevin, starts dating a woman named Marci. So, to prevent that from happening, they come up with a plan to get Marci to dump Kevin.
"Nightmare on Carrie's Street"
Mary-Kate and Ashley switch costumes with Max and Brian, so that they can attend Carrie's Halloween party, from which they were banned by Kevin.
"The Heartbreak Kid"
Mary-Kate wants to get a pet, but she's had bad experiences with animals in the past, which makes Kevin a bit worried. So Carrie and Mary-Kate buy a homing pigeon, thinking this pet will actually stay alive. Meanwhile, Ashley is heartbroken when she finds out her crush, Taylor, has a girlfriend.
"You've Got a Friend"
Ashley makes a new friend, Nicole, leaving Mary-Kate feeling left out in the cold. Meanwhile, Eddie and Kevin's friendship is in trouble when Carrie tries to be a mediator during an argument.
Ashley is excited when a model search for a teen magazine takes place at their school, but Mary-Kate is chosen over Ashley.
After Kevin buys them a new telescope, Mary-Kate and Ashley snoop on their neighbors. They think that they witness their neighbor, kindly old Mrs. Baker, murder her elderly boyfriend, Mr. Fillmore. The situation gets even scarier for the twins when Kevin asks Mrs. Baker to babysit them, while he goes to a jazz concert with Carrie. Meanwhile, Carrie hears Kevin play the saxophone, and encourages him to perform for audiences, just like he did previously.
"A Very Carrie Christmas"
Carrie accepts Kevin's invitation to spend Christmas with him and the girls. Carrie brings a homeless man, Walter, as her guest to Christmas dinner. Sometime during dinner, everyone is shocked to find out that Walter stole all their gifts. But they appreciate it when they learn the truth about why he did it.
Mary-Kate and Ashley prepare for their first school dance. Mary-Kate wants to dance with Jeremy, but he tells her that he only knows how to swing dance. Carrie teaches Mary-Kate how to swing dance. At the dance, however, Mary-Kate learns that Jeremy doesn't know how to dance at all - he lied to her because he wanted to impress her, and have an excuse for actually asking her out to the dance. Meanwhile, Kevin chaparones the dance.
Mary-Kate and Ashley begin arguing more frequently, which causes them to move into separate rooms. They soon learn that they miss each other, and move back into the same room. Meanwhile, Kevin's doctor and Carrie begin dating. Soon, she thinks that her new love interest wears a bra, which leads to embarrassing moments for both Kevin and Carrie.
"My Boyfriend's Back"
Carrie's ex-boyfriend, Alex Reardon, is back in town, and Carrie feels that she must make herself look as successful as he is. Carrie convinces Kevin to pretend to be Carrie's fiance to make Alex jealous. On the same night when Carrie and Kevin are out, the twins have a party that doesn't go quite as planned.
"No Man's Land"
Mary-Kate is forced to teach Ashley all about sports when she develops a crush on Eric, an avid sports fan. Meanwhile, Kevin must apologize to Carrie when he causes waves in their "friendship".
"Carrie Moves In"
After being evicted from her apartment, due to Kevin not mailing in her rent check, Carrie discovers his basement, and offers to help transform it into her own apartment. But when the cost is too high, a dispute occurs between Carrie and Kevin, causing both of them to spend some time alone, and re-think about what to do. Meanwhile, Mary-Kate likes a boy in her karate class, but debates whether or not she should let him win when they face each other in a match.
"Mr. Right Under Your Nose"
After failing to raise all the money that was promised for her school fundraiser, Mary-Kate convinces Ashley to gamble the money that she did earn on a basketball game, in order to double her money, but it doesn't go exactly according to plan. Meanwhile, Carrie begins to feel jealous when Kevin ends up having a good time dating her best friend, Nancy. Now, Carrie has to figure out her true feelings for Kevin before it's too late.
Kevin is not pleased when his lazy brother, Matt (David Lascher), comes to visit. Kevin knows his brother is immature and unreliable, which becomes increasingly clear after an incident at a hockey game - or does it?
19"The Odd Couples"
Mary-Kate and Ashley have been paired up with male partners for a school assignment, in order to learn about marriage. Meanwhile, Carrie starts dating Matt, despite Kevin's advice to the contrary.
"When a Man Leaves a Woman"
Kevin realizes that he is bored with his inhibited girlfriend, Nancy, and agonizes over how to end the relationship. However, when he tries, Nancy misinterprets him, and becomes even more serious about him. Meanwhile, knowing how much Mary-Kate loved horseback-riding when her mother was alive, Carrie invites her to come along for a ride. Mary-Kate declines, puzzling Kevin. Also, Ashley gets into trouble when she secretly orders a handbag for Jennifer's party over the Internet using Kevin's credit card without his permission.
"The Goodbye Girl"
Carrie has plans for a spontaneous journey through South America for the summer. Before she leaves, the twins trick Kevin and Carrie into having dinner together at a restaurant. At the airport, Kevin is disappointed to see that Carrie is traveling to South America with a classmate. In the end, Carrie kisses Kevin, and then boards the plane.
"Kevin Burke's Day Off"
To be accepted as a member of the cheerleading squad, Ashley must pull a mean prank on Mary-Kate's new friend, Gabrielle. Ashley soon learns that nothing is worth doing something so mean to another person. Meanwhile, Carrie convinces Kevin to take a day off from work, and the two go to a ballgame together. But what will Kevin's boss say when he finds out?
Note: This episode premiered in July as a burn off, three months after the show's actual finale "The Goodbye Girl" aired in April.