After Bobby defends Millicent at school she rewards him with a kiss and he immediately sees sky rockets. This leads him to try to kiss her again but after seeing those sky rockets again, she delivers the news that she may have the mumps.

Both Robert Reed puts in double duty as Grandpa Brady as does Florence Henderson when she portrays Grandma Hutchins in an episode where the Brady kids play matchmakers and try to get Grandpa Brady and Grandma Hutchins together. However, their efforts may all be for naught when an argument erupts between Grandma and Grandpa during a romantic dinner.

The Brady's friends, the Kellys are in the middle of adopting one little boy and soon find themselves adopting a total of three boys all of different ethnic backgrounds and they soon find themselves dealing with racist neighbors.

Carol breaks the news to Mike that she's expecting and an eavesdropping Bobby and Cindy assume that she's pregnant and pass it along to the rest of the family. Unknown to them what she meant was that she's expecting her nephew, Oliver to move in with them over the summer while his parents are in Africa.

When an FBI agent makes a visit to check Mike's security clearance, Bobby and Oliver both become convinced that Mike is working on some plans for a top secret project. They later become suspicious of Sam and become convinced that he plans to steal the ""secret plans"" and pass them on to the Russians.

Marcia plants a bogus story in her diary to bait Cindy after she gets fed up with Cindy's nonstop snooping. The bait is a story about Marcia contacting a talent scout after submitting a picture of Cindy and the talent scout wants Cindy to be the next Shirley Temple.

Bobby, wanting to get rich quick, begins selling bottles of hair tonic and sells a bottle to Greg. However, Bobby runs for his life after the tonic turns Greg's hair orange, just days before his high school graduation.

Cindy has been cast as the fairy princess in the school play. She's excited that her mom and new dad will be able to see her in the production until she learns she can only invite one parent. Torn between who she should choose, Cindy fakes an injury to get out of being in the play.

The day after Carol reads Mike's horoscope, which states "a strange woman will enter your life tomorrow," Beebe Gallini enters Mike's office and proves to be a most difficult client. Soon, Mike finds himself spending more time at the office than at home with Carol and the kids.

Carol is secretly writing an article about life with the Brady Bunch for Tomorrow's Woman Magazine. But soon after sending the article in, she gets a rejection letter.

Alice has decided to take a well deserved vacation, but feeling like she's deserting the Brady family, she calls in her cousin, Emma. The Bradys are in for a big surprise when she turns to household into an army barracks.

Feeling immature because she is the youngest, Cindy feels that she isn't appreciated until she gets a mysterious letter from a secret admirer.

In a paper for English class, Greg writes about wanting to follow in his dad's footsteps and become an architect. When Mike, reads the paper, he is ecstatic and goes all out encouraging him unknown to him Greg just picked whatever career to write the paper. Meanwhile, Peter and Jan also explore careers.

Marcia has a crush on a boy who doesn't even know she's alive, at least not until she studies up on his favorite hobby, insect collecting.

After discovering he is the only Brady without a trophy, Bobby enters numerous contests in order to win one. Including, selling magazines and a televised ice cream eating contest.

When Cindy's doll, Kitty Karry-All turns up missing, she accuses Bobby. This leads to a mock trial with Alice as the judge to determine Bobby's guilt or innocence. Then later Bobby's kazoo turns up missing and he blames Cindy.

When Bobby falls from a tree and sprains his ankle, he devolops a fear of heights. This prompts the Brady family to try to cure his fear.

When Bobby gets a set of drums he drives the family up the wall. Meanwhile, Peter is made fun of for being in the glee club by his football teammates.

Peter is determined to get the part of George Washington in the school play but the teacher thinks Peter would be better in the role of Benedict Arnold. When his friends start making snide comments about it he decides to get himself kicked out of the play.

Peter is ecstatic when he gets a job at Martinelli's bike shop. However, his wanting to do a thorough job inhibits his speed and work begins piling up as well as customers begin to customers demand their bikes. This leads Mr. Martinelli to give Peter the axe.

Both Bobby and Cindy have to opportunity to try out to be on a televised children's quiz show if they get a certain score on a written test. However, an overconfident Bobby doesn't study at all and fails while Cindy is chosen and her ego alienates the rest of the Brady kids.

With more and more of the girls belongings being moved over from storage, the boys become fed up and take to their 'No Girls Allowed' clubhouse in the backyard which sparks the first of many battles between the sexes. This leads the girls to try to build their own clubhouse.

Peter comes home from school with the measles, so naturally, Carol calls the doctor, her doctor, who happens to be a woman. Meanwhile, Mike calls his doctor, a man. Soon all the kids come down with the measles and the household is in an uproar in yet another battle of the sexes, as the girls want a female doctor and the boys want a male doctor.

While playing football in a vacant lot with Greg and Peter, Bobby discovers a wallet containing $1,100. When the girls learn about the boys' coup, they decide they want a cut of the money; this leads to yet another fight in the Brady household.

Jan's practical joking puts Greg's science project, a mouse named Myron, in mortal danger when he gets loose allowing Alice to catch a glimpse of him which leads to her calling the exterminator.