Teenager Patty Lane and her worldly identical cousin Cathy navigate family and high school life.
Cast:Patty Duke , Jean Byron , William Schallert , Paul O'Keefe , Eddie Applegate , Alberta Grant , Kitty Sullivan , Sammy Smith , Jeff Siggins , John C. Attle , Timothy Neufeld , John Spencer , Skip Hinnant , Robyn Millan , Harry Packwood , John McGiver , Alice Rawlings , Joanne Mariano
A new boy in town competes with Richard for Patty's affections. Patty's mom and dad take sides on which boy to give advice to.
Patty takes up the tuba and practices incessantly, much to the chagrin of the rest of the family.
Patty writes an advice to the loverlorn column for the school newspaper. But most of her readers are not happy with her advice, especially Cathy.
Patty, with Cathy and Ross, organizes a union in order to get more benefits around the house. So Martin and Natalie decide to form a union of their own.
In order to prove a point to her history teacher, Patty vows that she can live for one week like they did back in 1800.
Patty and Cathy battle each other over their new next door neighbor.
Patty and Cathy campaign for a family friend's run at a congressional seat. They are less enthusiastic when they disagree with his platform.
Patty gets invited to a college prom but her parents won't let her attend. Taking Cathy's advice, she decides to use a little psychology to get her way.
Patty feels the need for something more in life and decides to sign up for the Peace Corps.
Cathy falls for the new boy at school, despite all of the advice given to her by the rest of the family.
The school's football star has a huge crush on Cathy and she couldn't care less.
After some stocks that her father bought for her increases in value, Patty decides to sell stock in a new company: Patty Lane Inc.
Patty is looking forward to the father-daughter dance but is disappointed when her father gets called away on a newspaper assignment.
While Cathy is considered the front runner for student of the year, Patty, acting on the advice of her father, decides to take on more responsibilities at school. Her actions increase her chances at becoming student of the year.
Patty battles her arch rival Sue Ellen for the new boy at school.
Patty believes that she has witnessed a crime and now she thinks that the mob is going rub her out.
Patty believes that her parents are trying to marry her off to a man she doesn't even know. Her only recourse is to act as unappealing as possible in order to discourage the marriage.
Patty and Cathy's cousin Betsy comes to stay with the Lanes on her vacation from boarding school. After a while, Patty begins to believe that Betsy is trying to come between her and Cathy.
Cathy is chosen to show Sal Mineo around his old Brooklyn Heights High School, but Patty thinks the honor should go to her. Cathy relents and Patty gets a chance to act with Sal Mineo in a school play.
Patty decides to have a raffle to benefit the church bazaar. The prize? A date with Richard. But can Patty stand it if one of her rivals wins the prize?
Martin thinks that he is being phased out as managing editor of the Chronicle, just as Patty falls for his presumed replacement.
Ross is expecting his usual surprise birthday party. But the family has other ideas.
When Cathy is chosen to host a classical music program on a Brooklyn Heights radio station, Patty sees this as an opportunity to promote a new singing duo she has discovered.
After the Lane family discovers that their home played a part in the American Revolution, they learn that the local historical society wants to take over their house.
After Patty's success at getting a star to appear at last year's school prom, she gets selected to do the same for this year's prom.
Patty falls head-over-heels for her new science teacher, Greg Noble (Robert Goulet) - and her studying genetics of 19th century scientist Gregor Mendel only serves to convince her that their genes are a perfect match, and being Mrs. Greg Noble is her destiny.
Ross' pet frog accidentally finds its way into Patty's bed. This triggers a series of practical jokes that eventually involves the entire family, whether they deserve the practical joke treatment or not.
Patty mistakenly believes that Ross wishes to participate in a midget car race, so she dutifully proceeds, with Cathy's help, to build a car for Ross.
After Patty breaks a date with Richard, Cathy and Richard begin dating. This leads to some tension between the cousins, all the while Richard lets his newfound desirability go to his head.
Martin begins to feel he is losing touch with his daughter Patty and would like to spend more time with her. When Patty agrees Martin begins to realize that he may be getting more than he bargained for.
Cathy writes a letter critical of an editorial in her Uncle Martin's newspaper, not knowing that her uncle wrote the editorial. The resulting firestorm has Cathy worried about her future in the Lane household.
Even though her father forbids it, Patty wants to be a folk singer at the local coffee house. And brings Richard along as her manager.
Patty, because of her lack of cooking skills, fears that she is losing Richard to a rival. So Patty enlists Cathy to cook for her in order to get Richard back. But the plan backfires when Cathy is called away before she can prepare the meal.
Ross fears that he won't make the little league team, so the family takes it upon themselves to help Ross out.
Jealousy rears its ugly head when Patty craves the limelight shunned by Cathy, after she rescues a drowning boy.
Patty's father bets her that she can't remain silent for 72 hours. Patty takes that bet but later regrets it when it interferes with her spot on the debate team.