Harley is an engineering whiz who uses her inventions to navigate life as the middle child in a large family of seven kids.
Avid inventor Harley Diaz is all set to accept a community award, but first most devise a way to get her huge family of 9 out of the house and to the ceremony on time.
Harley's parents forget her birthday, so she devises a plan to use their guilt as a way to get the ultimate birthday gift.
To raise money to replace her family's broken tablet, Harley decides to rent out the family's couch to a foreign exchange student.
When Harley procrastinates on finishing her science project, it inadvertently leads to the Wi-Fi going out, leading her entire family to head out to the movies.
Harley tasks herself with creating an activity for the annual neighborhood block party, but finds it difficult to come up with the perfect idea.
Harley uses her creativity to convince her dad to hire her at his marina store. Once there, she unveils her newest invention, the "slushinator.".
Harley decides to go solo on a Mother's Day gift, rather than include the rest of her siblings.
Harley decides to host an outside slumber party to watch a passing comet with her friends.
When Dad goes out of town, Harley must find her mom a new friend after she becomes overly clingy.
After Cuff makes himself at home, Harley finds a way to get Cuff out of the house by getting him a job.
Harley helps Georgie secure a spot on the golf team. Meanwhile, mom puts the kids up to a cooking challenge when they complain about her food.
Harley and her siblings fend for themselves when their parents go away for the weekend. Meanwhile, Rachel uses Harley's help to make her friends jealous.
Ethan invests in Harley's latest invention!
Harley and Ethan try to take Daphne down!
Harley turns to Rachel for a ride to a contest.
The family throws Georgie a 15th birthday party!
The Diaz family star in their own reality show!
The Diaz family jumps in, slides down and wades right into the metaphorical deep end of a family vacation when Harley's winning invention scores the family a free trip to a waterpark, in the season two premiere of Stuck in the Middle.
Harley and Ethan partner up to make a TV commercial for their dad's store.
It's school picture day and in true Diaz fashion, things go awry for Rachel, Georgie, Ethan and Harley.
Harley's Slushy Shack faces new competition which escalates into a full-scale slushy war.
The kids organize a garage sale in order to make enough money to buy an above-ground pool.
The Diaz kids team up to save their family holiday traditions from disappearing.
After discovering a shocking truth about Beast's birthday, Harley throws him an epic party that causes a rift between the twins.
The kids must entertain themselves for an entire weekend without using technology or devices.
Harley, Rachel, Georgie and Ethan attend their school spring formal dance, while Lewie and Beast camp out at home in the backyard.
Harley tries to save Ellie from boarding school.
Harley and Suzy volunteer at a local retirement community.
Harley enters Daphne and Dad in a TV dancing competition to get her latest invention noticed.
The Diaz family hosts Olympic medalist, Laurie Hernandez, for a dinner that spins out of control.
When the parents leave it up to the kids to decide who will move into the new bedroom in the attic, the kids compete in a "Diaz Decathlon.''
The girls have to share their room with Daphne after her playhouse is thrown away.
Harley befriends the new girl in school, but the friendship becomes strained when Ethan befriends her too.
On Halloween, Harley becomes determined to prank Rachel, the one person in the Diaz family she hasn't been able to scare before.
When a superstar golfer shows up at the Bait and Bite looking for a place to stay, Harley decides this is the perfect opportunity to raise money for a dream family vacation.
Harley tries to prove her babysitting skills by watching Beast, Louie and Daphne on her own.
The Diaz family celebrates the best, worst, funniest and most Diaz-y moments of the past year during the annual family awards night.
Harley rallies her siblings and parents to take a trip to Florida to celebrate Christmas with their abuela, but in true Diaz fashion, things go awry. One rerouted flight, an unintended pit stop and a damaged rockstar tour bus later, the Diazes find themselves stranded in a small town without phones, credit cards or money, where they must compete with the town residents in an "Iron Elf" competition to get their bus repaired and make it to Abuela's in time for Christmas.
When Rachel apparently misses out on an incredible educational opportunity, her sisters are suspicious of how well she takes the news. Meanwhile, Ethan cashes in on his experience of living with four sisters by landing a job.
Georgie struggles filling into the oldest sister role.
Harley and Ellie host a winter break camp for kids.
Harley and Suzy come up with a new way to get along with their neighbors.
Georgie enlists Harley's help to break up with Wyatt.
Harley's latest invention causes havoc in science class.
When the Bait N' Bite is robbed, the Diaz kids use their resources to track down the culprit.
Under Abuela's watch for the weekend, the Diaz kids are committed to making her visit disaster-free, that is, until Harley learns that Ethan spilled her deepest secret.
The Diaz's must deliver a luxury yacht on spring break. They live it up until they dock at the port next to the dreaded Pillman family.
When Georgie fails to make the basketball team this year, Harley helps her cultivate a new passion instead.
The family preps for Ethan's latest short film premiere party, while also navigating a weekend visit from annoying neighbor Aidan.
When Harley volunteers to oversee Daphne's first sleepover, she uncovers a truth about Daphne that she never expected.
Harley notices the Diaz kids aren't as tight-knit lately, so she uses her Lock Squawk invention to turn the attic into an escape room and acts as the game master.
Harley realizes that she had a great time hanging out with a surprisingly sweet and generous Aidan, despite a chaotic day; Georgie calls Harley out for crushing on Aidan.
Aidan gets Harley a special gift.
When the family car rolls into the garage and causes severe damage, Tom and Suzy look for a culprit; Ethan and Harley don't have alibis, so they head to Diaz Court.
Harley enlists the help of the Littles to tackle what's left of her Buck-Kid List before she becomes an official adult.
