Pam Crandal has a great new job. She is helping to school two new ponies. Pam loves training the ponies, but she must work long hours.
Pam worries that her pony, Lightning, doesn't understand why Pam is spending so much time with other ponies. Her Pony Pals, Lulu and Anna, are getting mad that Pam is too busy for trail rides with them. Will Pam have to stop being a Pony Pal?
Pam and her mother purchase two new ponies from Mr. Olson because Ms. Crandal needs more ponies for her students as a riding instructor. The ponies are Daisy, a palomino Shetland, and Splash, an Appaloosa with markings on his back that look like splatters of paint. Behaviorally, Splash has lots of energy but is used to getting away with stuff, and Daisy is sweet but lazy and slow. Since both ponies need more training to be used with students but Pam's mother is too tall to ride them, she offers to pay Pam to train them. Pam agrees because she wants a new saddle to replace her worn out one. However, Pam's new job means she can't go riding with the Pony Pals, and she can't give her pony, Lightning, the usual amount of attention. Pam feels left out from Pony Pal adventures and guilty for neglecting Lightning.
To avoid missing out on trail rides with her friends while still doing her job, on Saturday after a week of working with Splash Pam decides to take him out riding with Anna and Acorn and Lulu and Snow White, instead of Lightning. However, it doesn't go well because Splash is too hard to control, and strains to go faster than the ponies ahead of him. Anna and Lulu make Pam promise not to bring Splash next time. Pam hopes she can keep this promise and her job.
The next day, Sunday, the Pony Pals meet to go trail riding again and this time Pam brings Daisy, because she hasn't been on the trail yet. Anna and Lulu are irritated that Pam brought Daisy because of what happened the previous day with Splash. However, Daisy has the opposite problem that Splash has - she is lazy and slow, and can't keep up with Acorn and Snow White. The three girls fight and Anna and Lulu accuse Pam of working too hard and ruining their plans, and Pam thinks they are being selfish.
After riding Daisy, Pam goes to finally ride Lightning. However, Lightning is acting nothing like her usual self, and for the first time ever, Pam is frightened of her pony. Pam wonders if Lightning might be sick, but knows Lightning does not look sick. So she concludes Lightning must be mad at her for neglecting her to ride the other two ponies.
Anna and Lulu come back and and make up with Pam over their fight earlier. Pam tells them how Lightning has been acting, so they decide Lulu should try to ride her if she is mad at Pam. However, Lightning still gives the same fierce look. Just then, Fat Cat comes by and Lightning stays still and does not snort at the cat. The girls discover that what Lightning has been doing is protecting Fat Cat's new kittens. After Fat Cat brings each of her five kittens out of the straw, the girls decide to set up a box and food for Fat Cat in the feed room closet so she and her kittens jave somewhere to go.
When Pam's mom comes home and discusses her progress with Daisy and Splash, Anna and Lulu finally realize that her job has been a lot of work, and they offer to help Pam. Pam tells them the next day at school that she's offering them a part-time job, and her mom will pay them. The girls meet at the Off-Main Diner to plan how they will train Daisy and Splash. They plan to take the two ponies out together, without Acorn, Snow White, or Lightning, and to have one person ride Splash while the other directs him with a lead rope. When the girls take the two ponies out the next weekend, both are much better behaved. Mrs. Crandal watches Pam working them and determines that they will be good enough for her students who will start the next week, so Pam's job is over unless the ponies need an occasional refresher course.
- Fat Cat- a pregnant cat Lulu and Anna find on the trail, who has five kittens and becomes the Crandal's new barn cat whose job it is to catch mice
- the Crandal's barn cats Jezebel and No Tail, who don't seem to do a great job of catching mice