As Christmas approaches, Sue keeps a holiday secret from the family. After agreeing to watch the neighbor’s three kids, Brick finds himself trying to hide from them as they had such a good time that they keep wanting to come over and play. Mike doesn’t know how to react when Bill Norwood gives him a Christmas gift for the first time ever,

The series concludes as the family escorts Axl to Colorado. Meanwhile the long affair of the snow globe and its relation to Sean and Sue's relationship comes to a head.

The Heck family learns about Darrin’s marriage proposal to Sue…as well as her response. Meanwhile, Axl attempts to use his intro to Psych class to cure Brick of all of his quirks and tics.

Each member of the Heck family finds themselves in situations reminiscent of "The Twilight Zone."

Axl is startled to run into nearly all of his former flames at a St. Patrick's Day party leaving him to wonder if it is a sign about his love life; Brick buys an old microfiche machine at a library sale, leaving Frankie and Mike less than thrilled.

Mike's friendship with Bill Norwood is in jeopardy after Bill gets angry when Mike poaches his plumber at a reduced rate; Frankie is disappointed when Sue refuses to tell.....

Sue's senior year, the "Summer of Sue," begins with the premature removal of her braces. Meanwhile, Axl finally beats Mike in basketball and Brick tries to find the perfect backpack for school.

Frankie and Mike are shocked when Brick announces that he wants to go to his school's fall dance. Axl has a week to declare his major but has no idea what it should be. Sue attempts to show she's more mature by drinking loads of coffee.

Brick invites a girl over to the house for Halloween, Sue tries to raise money for college with a pumpkin patch screening of "It's the Great Pumpkin, Charlie Brown," and Axl accidentally gets locked in the library.

Frankie has to wash dishes with a hose after the kitchen sink packs up. Sue has to learn a complicated dance routine so she can pass phys ed.

Frankie acts like a teenager when she hangs out with Pam Staggs, a former classmate who was popular in high school. Meanwhile, Brick surprises Mike by winning an athletic award; Sue pursues some odd hobbies; and Axl seeks a date with Devin Levin.

Frankie and Mike struggle to stay awake when watching a movie during a cozy date night at home. Meanwhile, a handsome mall employee asks Sue to her senior prom and Axl and Brick hope to find success with a barbecue sauce they've created.

Sue prepares for her graduation and worries the day won't go perfectly. Meanwhile, Brick gets the opportunity to skip a year in school and Axl grows concerned about Devin's fun summer pictures she posted on social media.

Sue's excitement about moving into the dorm to start college is tempered when she accidentally burns her hair and must cut it short. Axl isn't interested in helping with Sue's move. Frankie discovers she's not sad about Sue moving out of the house while Mike overwhelms Sue with financial and safety guidelines. Brick is clueless when Cindy tells him she wants to take their relationship to the next level.

Dreading the fact that they are always late to church and end up in the overflow room, Frankie makes the decision to have the family watch a Christmas Eve service on TV from the comfort of the Heck house. But a string of events make their evening anything but a peaceful, silent night.

While the Hecks take Brick to his first movie in a theater, Mike and Frankie fight over a conversation with friends, Sue runs into an old crush who has some surprising news, and Axl discovers that he shared an awkward moment with a friend.

Frankie's excited to take care of Sue and Axl after they both have their wisdom teeth removed; and Brick lays down new house rules for his siblings while they're back home. Meanwhile, Mike learns the diaper business was Rusty's ex-wife's idea and becomes furious when he finds out she may be entitled to all their profits.

The Hecks decide to take a Spring Break vacation with the Donahues, but Frankie soon discovers that both families are going through their share of big problems.

Frankie's plans to have a peaceful backyard lanai are ruined by her new neighbors' loud children. Axl and Hutch begin a new food business on campus. Sue and Lexie make plans for next year after they win the dorm lottery.

Frankie decides that April is not good enough to be with Axl and does anything she can to keep her out of the annual family Christmas photo. Frankie must fight for Axl's attention when he announces that he will be spending Thanksgiving with April.

After discovering that he doesn't have a decent suit to wear for upcoming business interviews, Frankie is thrilled when Axl agrees to let her take him shopping to help him pick out a suit; and when Mike threatens to do away with the family summer pool if Sue and Brick don't start using it, they begin to worry that he and Frankie may take even more things away from around the house from their childhood that they don't use anymore as they edge towards adulthood.

Frankie looks for the gift she bought for Axl's graduation; Sue decides to make a video for Mike's birthday; Brick asks Axl to help him get in shape after Cindy saves him from a bully.

Frankie, Mike and Brick begin to notice that their luck has changed dramatically for the better after the Prairie Scouts accidentally paint the Donahue's address on their curb; and after missing his final college test before he graduates, Axl pleads with his teacher to let him take it, otherwise he won't be able to graduate. Meanwhile, Sue confides to Brad that her sophomore year in college was kind of a letdown. But a chance to speak to students at her former high school about college life leads her to a realization about her status as a student while at Orson High. A talk with Brad leads into an impromptu musical number about Sue's many accomplishments over the years.

Frankie and Sue are devastated when Axl informs them that he's not going to church; Mike goes to war with the Glossner kids after they keep defacing his giant inflatable snowman; Brick attempts to wrap his first present.

After Brick attends a Bar Mitzvah and questions when he'll officially become a man, Mike attempts to help him become more responsible in his quest to manhood. Meanwhile, Sue exudes a little too much enthusiasm as she tries to flirt and find herself a boyfriend, and Axl and Hutch find themselves a new home in the form of a Winnebago.