Paul Fisher, an eighth grader with bad eyes, is afraid of his older brother, Erik. As Paul packs up his house in Houston, he has a terrifying vision of Erik leaning out the window of a car, wearing a ski-mask, swinging a baseball bat at Paul’s head. He writes about the strange vision in his journal; this mysterious journal entry is how the diary-novel of Tangerine begins.
Paul and his family are moving from Houston to Tangerine County, Florida—a region known for its tangerine groves. When they arrive, Paul sees piles of tangerine trees smoldering in great heaps. Many of the groves, it turns out, are being slashed and burned to make way for new housing developments like the one that the Fisher family moves into: Lake Windsor Downs, a sterile, wealthy development where all the houses the look the same.
When they settle in, Mrs. Fisher joins the Lake Windsor Housing Association and becomes the head of the architectural committee. Mr. Fisher will be the new director of civil engineering for Tangerine County. Erik will be the kicker for Lake Windsor High football team.
Paul’s parents are obsessed with Erik’s football career—so much so that they don’t seem to notice the sinister things about Erik that Paul notices. They also don’t seem to pay any attention to Paul. Paul loves to play soccer; he’s the goalie. Because of his bad eyes, he has special goggles that he wears when he plays. But when Paul signs up for Lake Windsor Middle School, his mother tells the principal that Paul needs help because he is legally blind. Because of this, Paul ends up with an IEP (an individualized education program) and he’s not allowed to play on the soccer team. Paul makes friends with Joey Costello, but he’s still incredibly depressed by not being able to play soccer. His parents, though, are more concerned with Erik’s life.
Erik makes friends with Arthur Bauer; as soon as Paul sees them together, he knows that Arthur is going to play a bad role in Erik’s life. Erik, Paul knows, has a way of manipulating people. Paul can tell that Erik is going to get Arthur to do bad things for him.
The first sign of Erik’s sinister ways comes when there’s a terrible accident. Another football player, Mike Costello, gets struck by lightning during practice. Paul sees Erik and Arthur laughing about the tragedy.
Tangerine is a region of wild weather. There are constant muck fires smoldering under the ground; there’s constant rain and flash floods; and the county, it turns out, has the most lightning strikes in the entire country. One day after a torrential storm, a sinkhole opens up at Paul’s school and swallows one of the portables. No one dies, but the school grounds are condemned. Paul has to go to another school. He’s thrilled: this means he can play with another team—without an IEP.
Paul demands that his parents let him go to Tangerine Middle School. They’re nervous, because the school is in a rougher, poorer town of Tangerine. It’s nothing like their sterile housing development. But it has a soccer team—a good soccer team. The War Eagles, it turns out, have some of the best players in the county. Many of the players are girls. Tough girls. The boys are tough too. At first they’re suspicious of Paul. But little by little, Paul comes to prove himself on the field. He also likes the kids’ sense of humor. When they tease him, he teases back. Everyone in Tangerine is rough and honest, and Paul loves it.
The kids of Tangerine come from poor working families—tangerine-growing families. All the kids help out on their families orchards. As Paul gets close with Tino and Theresa Cruz, he comes to help out in their tangerine groves. Tino and Theresa have an older brother, Luis, whom they adore. Luis has been developing a new kind of tangerine called the Golden Dawn. Paul loves spending time and working outdoors with the Cruz family. He also loves how loyal they all are to each other.
Erik on the other hand, is malicious and cruel. One day after the Cruz kids begin to trust Paul, they come over to his house to work on a science project. Erik comes out and teases the kids for being poor farm laborers. Tino stands up to Erik, but Erik smacks him across the head and makes him bleed. Paul is devastated, but he doesn’t know how to stand up to Erik. He’s terrified of Erik. Luis comes to the Lake Windsor high school the next week to avenge his little brother, but Erik gets Arthur to hit Luis over the head with a blackjack. Luis hits the ground, bleeding. Paul has been hiding under the bleachers. He witnesses Luis bleeding on the ground. A boy named Antoine Thomas (the real star of the football team) helps Luis up.
The Cruz family loyalty becomes more apparent during a week when the temperature drops in Tangerine County and the kids need to work through the days and nights to save their oranges from freezing. Paul hears about what’s happening on the groves and he goes over to help out. They work through the night, lighting bonfires, hauling wood and diesel, and digging up baby trees to bring them inside to save them. It’s desperate, difficult work, but Paul goes for it. Luis takes Erik aside and thanks him. Paul apologizes for his horrible brother.
Mr. and Mrs. Fisher are excited about the prospects of Erik’s football scholarships. But in the last game of the season, Antoine Thomas doesn’t play the ball to Erik and Erik doesn’t get to shine on the field. There are other problems in their lives too: a termite infestation is taking over the Lake Windsor housing development, so the houses need to be sprayed and tented. There’s also a mosquito infestation because some of the homeowners tried to put out the underground fires by pumping water into them. Then, all the termite-infested houses get burgled, when no one is living in them. On top of that, someone begins spray-painting the outer walls of the housing development. The homeowners imagine that it’s kids from town.
Luis dies of an aneurism a week after getting hit over the head by Arthur. Paul is devastated, but the Cruz kids are more devastated. They refuse to see Paul. During the high school award ceremony, Tino Cruz and Victor show up and attack Erik while he’s getting his award. They get Arthur, too. Paul’s in the audience; he knows that they’re taking revenge for Luis. The football coach tackles Tino, but Paul runs down and jumps on the coach’s back, freeing Tino, who runs out with Victor.
Paul runs back home. He’s standing behind his house when Erik and Arthur find him. But as he faces them, he’s not scared. He tells them that he knows that they killed Luis. They’re terrified and drive away. Then Paul has a flashback from his childhood. He remembers how Erik used to have a sidekick named Castor. Erik and Castor spray-painted the walls of the development and got caught. They blamed Paul for ratting on them; as punishment, they took him into the garage, held his head, pried his eyelids open, and spray-painted his eyes. That’s how Paul’s eyes got damaged.
Paul confronts his parents. They are ashamed. They tell him that they hid the truth about his eyes from him because they didn’t want him to hate his brother. He asks them if they wanted him to hate himself instead. The next day Antoine Thomas tells the media that he comes from Tangerine—not Lake Windsor. He’s been falsifying his address. The coach and all the parents knew; it was an open secret. As a result, all the wins of Lake Windsor High are forfeited. Erik’s football dream comes crashing down.
It turns out out that Erik and Arthur were the ones robbing the termite houses. Paul’s mom holds a meeting with the neighbors and everyone is horrified. When they’re at the meeting, the police come to arrest Arthur for the murder of Luis Cruz. Paul announces that he witnessed it happen and that Erik was the one who told him to do it. Erik admits this is true. The truth has come out. The façade of football glory and the perfect life in Lake Windsor has been torn away. Paul gets kicked out of Tangerine High for attacking the coach, but he vows to play for the War Eagles next year. He’s stronger than ever because he spoke the truth.