The Ingalls settle on the banks of Plum Creek in Walnut Grove. To get the farm set up, Charles must take on several jobs at once. He promises one person that if he didn't get the job done in the specified time, the person could have his oxen.

Laura and Mary start school for the first time. That is where they meet Nellie Oleson. Since Laura hasn't been to school before, she tries especially hard with her schoolwork. The students have to write an essay to present in front of the class. Laura recites what she would have written on the paper if she could have, instead of what was actually written on it.

Laura connects with a sweet, shy classmate named Olga Nordstrom, who happens to have been born with a short leg. Charles has an idea that can change Olga’s entire life, but the challenge will be convincing the child’s stubborn widowed father.

Believing that her jealousy was responsible for her infant brother's death and that her parents would rather have a son than a spare daughter, Laura climbs the highest hill she can find, hoping to get as close to God as possible to ask Him to take her instead and return the baby boy to the family. While Charles and Mr. Edwards desperately search for her, Laura meets Jonathan, a mystical mountain man who seems to have been sent purposely to guide her through this life-changing experience.

The Christmas holiday is approaching and the members of the Ingalls family go about their holiday shopping in secrecy. Laura is able to buy her mom a stove that she wanted after she sells her horse to Mr. Oleson.

Several people in Walnut Grove get very sick. A quarantine is set up in the church while the source of the illness is being sought.

After Ms. Beadle sprains her ankle, Caroline becomes the substitute teacher. Caroline takes a special interest in helping an older student, Abel, learn to read. One day Mrs. Oleson shows up and causes Abel to quit school. Because of this Caroline quits, but returns after she convinces Abel to give school another chance.

Caroline becomes pregnant. Shortly after the baby is born, he becomes ill.

In the beginning, things look very good for the Ingalls until a bad hailstorm ruins their crops. Charles and some other farmers must leave to look for work. They end up working in a quarry. While Charles is away, Caroline is able to get the women of Walnut Grove to join together to harvest the remaining crops.

While Charles is in Mankato, he runs into Mr. Edwards and invites him to come to Walnut Grove. Caroline tries to match Mr. Edwards up with Grace Snider, but instead she just ends up in the way since Mr. Edwards is able to charm Grace all by himself. Although there are a couple problems that must be overcome, things turn out for the best in the end.

The town becomes divided when Mrs. Oleson offers to buy a bell for the church, but only if she can put up a plaque. The differences and arguing begin to affect the school children. A mute craftsman, Tinker Jones, steps in and with the help of the school children, is able to make a bell.

While studying for an optional history exam in the barn, Mary accidentally knocks over a reading lamp and starts a fire. Caroline punishes Mary by telling her she couldn't take the exam. Mary doesn't tell Ms. Beadle this until the day of the exam.

When it is found out that a young boy, Graham, is being beaten by his alcoholic father, John, Caroline takes care of the boy while Charles stays with John to try to get him to stay sober.

The Ingallses have to seek shelter when a blizzard hits. There they meet an Indian who helps them out. A marshall, looking for the Indian, comes by...

Charles allows Laura to adopt a baby raccoon, Jasper. After being caged, the raccoon bites Laura and Jack and runs away. The family fears that Laura and Jack might have rabies until a healthy Jasper returns.

Charles and Caroline decide to go on a second honeymoon and leave Mr. Edwards in charge of the children. The honeymoon doesn't turn out very well because Caroline keeps worrying about the children. Back at home, Mr. Edwards has his hands full with Carrie.

Walnut Grove celebrates this great day with several different competitions. There are very competitive spirits between the Olesons and the Ingallses.

After a major disagreement, Nels and Harriet go their separate ways. Many people in town try to get the two back together.

A college-educated farmer named Joe moves to Walnut Grove with his pregnant wife. He tells the Walnut Grove-area farmers of a new hybrid of corn that would produce good crops, to which the farmers are very enthused. They decide to buy some of this new seed. While on the way back to Walnut Grove with the seed, Joe gets into an accident, as the farmers wait for his return.

Dr. Baker and Harriet's niece, Kate, fall in love with each other. Then their age difference becomes an issue.

After her friend dies, Miss Amy, an old lady, convinces the Ingalls and Doc Baker to help her stage her own death. Amy thought this was the only way to get her family to come and see her.

A traveling circusman, O'Hara, comes to Walnut Grove and tries to get everyone to believe he has magic healing powders. However, he is really found out when Mrs. Oleson almost loses her life when she tries his healing powders instead of having an operation.

Laura falls in love with a new student, Johnny Johnson. Johnny, who is a lot older than Laura, is interested in Mary instead. Although Mary is not interested in Johnny, Laura's actions cause tension between the sisters. When Charles finds this out, he is appalled that either of his girls is involved with Johnny.

Johnny Johnson leaves to ""see the world"" and Mr. Edwards goes along with him to keep him out of trouble. Johnny meets up with a girl who is able to trick him out of a lot of money. Mr. Edwards talks to this girl to try to have her convince Johnny to go back home.