Sam Wilson, a fifteen-year-old math prodigy with dyslexia, moves with her architect mom from San Diego to Portland. She falls in with five kids who call themselves the Brain Trust and compete to have the best grades. She falls in love with Nate Larson, one of the members of the group, who becomes her Spanish tutor. Sam wants to keep the fact that she's practically illiterate a secret from every member of the group except Nate, but that soon becomes impossible.
Counting to D contains examples of:
- The B Grade: The Brain Trust all made fun of Nate when he got a B+ on an English paper last semester.
- Child Prodigy: Sam passed algebra when she was still in fourth grade.
- Disappeared Dad: Sam's dad, Randolph Wilson, is a painter so famous he's in Sam's art history textbook, in the chapter on modern impressionists. He also has ADD and dyslexia. Instead of taking Ritalin, he self-medicated with vodka, leading to many drunken arguments between Sam's parents. After Sam was diagnosed with dyslexia at age seven, he moved to New Mexico, saying he wanted to paint the desert and Sam would be better off without an alcoholic father. Sam still has a picture he painted of her on the beach at age four.
- First Kiss: After Nate and Sam kiss, Sam is surprised to learn that it's his first as well as hers - even though he's a senior, no girls ever wanted to talk to him except his childhood friend Lissa, who he isn't attracted to.
- The Glorious War of Sisterly Rivalry: Invoked by Lissa Banks, one of the Brain Trust members, and her younger sister Kaitlyn. They come from a competitive family, and eventually they decided to stop competing for the same title. Lissa has perfect grades and wants to be the smartest kid in school. Kaitlyn obsesses over clothes and dates only the most popular boys. Kaitlyn is actually smart too, but she doesn't take any advanced classes because it would ruin her image.
- How Dad Met Mom: Sam's dad was hired to create a sculpture as part of the same public works project that her mom was the head architect for. They had similar artistic visions, and after the project was over, they decided to get married.
- I Just Want to Be Normal: Sam tells Nate that she wishes she was normal, like Kaitlyn. Nate tells her that Kaitlyn isn't really happy and says, "She's invented this persona, this 'normal teenager' image, as you so nicely put it, and now she's totally trapped. She can never be herself, 'cause she's too busy being a caricature of what she thinks people want and expect."
- Limited Wardrobe: The physics teacher, Mr. Maxwell, has about a dozen copies of both the green button-down shirt he wears when it's cold and the blue t-shirt he wears when it's warm.
- Married to the Job: Sam's mom has been unemployed for the last eighteen months, and spent as much of that time with Sam as possible. Now that she's employed again, she throws herself into her work, leaving Sam home alone most of the time.
- Moving Angst: Sam is heartbroken about having to move away from her only two friends, Gabby and Arden. Gabby tells her that now is her chance to leave behind her uncool reputation, but Sam doesn't think she'll be able to make new friends at all.
- Photographic Memory: Sam has an audiographic memory, allowing her to memorize her textbooks by listening to the audiobooks.
- Poster-Gallery Bedroom: Kaitlyn's bedroom is covered in posters of Justin Bieber, Justin Timberlake, and other people who look like they're named Justin.
- Trauma Button: Whenever Sam smells turpentine, alcohol, or acrylics, it reminds her of what she smelled the day her dad left. At a party, she talks to a boy who spilled turpentine on his shirt after art class, and the combination of smells causes her to curl into a Troubled Fetal Position.
