"It's someone who basically makes all their medicine out of herbs. She even grows a bunch of her own stuff." (3.25-27)
Laurel's mom has clearly spent a lot of time acquiring the knowledge to become a master naturopath, especially since she's practicing professionally. We're thinking it takes a combination of practical knowledge that you gain through experience, book learning, and maybe even some school. Anyway, between Laurel's mom being a naturopath and Laurel's dad being a bookworm, we're guessing that this is a family that really values knowledge.
"These are definitely plant cells, Laurel," David said, squinting at his microscope.
"Are you sure?" Laurel asked, taking her turn looking at the cells she had swabbed from the inside of her cheek. But even she recognized the thick-walled, square cells that dotted the brightly lit slide. (10.42-43)
It's kind of a running gag through the book that Laurel is just awful at biology. David must be rubbing off on her, though, since he's so awesome at biology and they're spending all this time together. If even she only has the basic biology knowledge needed to ID her own cells as plant cells, clearly she's not doing too badly on that front.
Laurel hadn't found a single source that talked about faeries being anything like she was. The closest she'd found were dryads—wood spirits—and they were just the spirits of trees. (11.138)
Another running gag in the book is just how ignorant humans are about faerie life, since they apparently always get the facts wrong. Since Laurel knows she is a plant (or something very like a plant), she tries to find similar accounts of faeries in stories and folklore, but pretty much fails except for learning about dryads. And we think dryads are cool and all, but since they're spirits and Laurel is very much a person in a body, it's not very helpful.
"There's always someone who secretly believes in myths and legends; or at least parts of them. Those are the people who will look beyond the obvious and see things in this world that are truly wonderful […] But they won't say anything, even if they do. Because the rest of us who view the world as scientific wouldn't see the truth if it was posted up on a billboard." (12.125)
Very wise words, David. Sometimes knowledge is passed down in mysterious ways, hidden in stories that don't seem true on the surface. Heck, even scientists admit that they don't know everything about the universe yet. There are still a lot of mysteries out there, and keeping an open mind about them can help you find hidden and beautiful things.
"Tell me about the magic," she said, changing the subject. "Can you fly?"
"No, like the wings, that's just folklore." (13.98-99)
Here Tamani seems to be using the word folklore to mean a falsehood or lie, and that's not always the case (in the academic world, folklorists consider folklore to be expressive culture, which might be true or false depending on what kinds of stories and traditions you're dealing with). But it's interesting to wonder, like Laurel does, what sorts of traditional knowledge passed down about faeries has a basis in truth. Bummer about the flying, though.
Tamani's hand tightened on her shoulder. "You've been very, very lucky. If he'd have realized what you were before, you'd probably be dead right now." (21.48)
Turns out lack of knowledge can save your life—if you're a faerie interacting with trolls that don't know you're a faerie yet, that is. According to Tamani, Laurel was really lucky that Barnes never guessed she wasn't human. There was always some kind of strong masking scent around, like the antiseptic smell of the hospital, the bonfire David had been at the day Barnes came to the house, or David's blood when the two of them got captured. Maybe Laurel should just start wearing blood-scented perfume.
Jamison nodded. "And he knows where you live. You must be on your guard. For your parents' sake as well as your own. I am appointing you as their protector. Only you know the secrets that can keep them alive." (23.83)
Oh Jamison, why you gotta be so mysterious while doling out wisdom? What secrets does Laurel know that will keep them alive? It sounds like he's talking about more than "you know that you're a faerie and that Avalon exists" knowledge, but he doesn't go into more detail on what he means. Knowledge is power in this world, and like Laurel, we're a little sick of being in the dark about all these important faerie secrets.
"Guard it carefully," he warned. "I don't know for certain that we have another Fall faerie strong enough to make an elixir like this. Not yet." (23.86)
Again with Jamison being wise yet a bit elusive. As one of the leaders of the faerie folk, he has to take into account what his people are capable of before giving away the products of their knowledge and work (like the elixir). It seems like the knowledge and magical skills required to make powerful elixirs are a big deal, and if Jamison is not sure whether they have the capability to make more of this potion, well, that just makes it an even bigger deal.
"How'd your mom take it?" she asked.
David laughed. "Pretty well, considering I lied through my teeth. I told her I left my phone in the car all night and we slept in your dad's room." (24.60-61)
Teenagers often feel that the less their parents know about their lives, the better. This is especially true for David, since he doesn't want his mom to worry about the fact that he was almost drowned by trolls the previous night or had to play chauffeur to a critically wounded faerie sentry. Stuff like that.
"Don't you know how much I wish I could stay? I love this forest… I love being with you. Hearing about Avalon, feeling its magic in the trees. Every time I leave, I wonder why." (25.58)
Learning about her faerie heritage is having some pretty strong effects on Laurel, and we're not just talking about her intense yet confusing feelings for Tamani. She's hungry to learn more about Avalon and faerie life in general. She's been denied knowledge about her identity for so long as part of this whole gambit to have her inherit her human parents' land, so it's no wonder she's eager to learn.