When writing for a specific age group, you want to be relatable. If you’re writing a chapter book series, you’re going to have to be relatable a lot. Can you cover ten topics? Twenty? Here’s a shortlist of fifteen common topics I’ve seen across different chapter books series. More importantly, we can see how each one is adopted by each series.

Some authors use a topic for the premise of an entire series, while others use it for just one book. I’ll cover every series I’ve read that includes each. You might start to notice a lot of series cover the same topics. If you can be interesting once, other people can too.

This might contain light spoilers for certain series, so don’t say I didn’t warn you.

Losing a Tooth

This is a pretty specific category, but it came up three times, and making a broader “Medical” category doesn’t add much. All kids lose teeth so it’s something very relatable.

Isadora Moon Meets the Tooth Fairy – Isadora is scared of going to the dentist. When her tooth falls out, she meets a fledgling tooth fairy that convinces her to go. During the events of the books, Isadora struggles with what do do with her tooth. Should she give it to the tooth fairy like her fairy mom would or put it on display like her vampire dad?

The Adventures of Sophie Mouse: The Missing Tooth Fairy – Sophie loses her tooth, but after multiple nights, the tooth fair doesn’t come. Did Sophie do something wrong, or is the tooth fairy missing?

Junie B. Jones: Toothless Wonder – Junie refuses to put her tooth under her pillow, because she doesn’t know who the tooth fairy is or what they’ll do with her tooth.

Mermaids

A very common focus in a lot of kidlit formats. Chapter books are no exception.

Emerald series – The star of her own series, Emerald is a mermaid that lives in an underwater kingdom. Her mom was recently remarried to King Alder, making her a princess with two sets of parents. Being a princess with new parents are both things she is not used to.

Isadora Moon Goes on Holiday – When Isadora wins a beach vacation for her family, she meets a mermaid who helps her rescue a turtle. In Under the Sea, Isadora meets Emerald, which prompts her above series to start.

Itty Bitty Princess Kitty: Mystery At Mermaid Cove – The mermaids in Lollyland have stopped singing. Itty goes to investigate the cause. She meets a mermaid friend and together they find the source of the issue.
Mermaids also play a minor role in other books in the series, as their singing tells the time at the top of every hour.

The Princess in Black and the Mermaid Princess – Princess Magnolia meets mermaid princess Posy while on vacation. Posy asks for her help fighting a kraken, but fighting a bad guy underwater is harder than she thinks. This is your typical Princess in Black story, but now it’s underwater!

Unicorns

I’m including this one because it’s one I thought would come up a lot more than it did. It seems Unicorns, unlike other magical races like Mermaids and Dragons, aren’t seen much in chapter books. Maybe I should change the title of the article.

Itty Bitty Princess Kitty series – One of Itty’s best friends is Luna, who is a Unicorn.

(I haven’t read Mermicorns yet so it doesn’t count.)

School

This might be cheating a bit, because most kids go to school. Not every chapter book protagonist goes to school though, or at least we don’t see them do that much. It’s more of a category due to the ones that don’t, more than the ones that do. So let’s start with those.

Basically No School
Magic Tree House, Emerald, Itty Bitty Princess Kitty, Dragon Girls, and Daisy Dreamer feature kids that are known to go to school. Due to the nature of these series though, they usually don’t. Jack and Annie are off time travelling in the tree house. Emerald and Itty are busy going on adventures in and around their kingdoms. The Dragon Girls are off saving the Magic Forest. Daisy is romping around in the WOM with her imaginary friend.

Jack and Annie are seen at school exactly once. Emerald, Itty, Daisy, and the girls of Dragon Girls all go to school occasionally, though the setting isn’t normally the main focus of any given book. It’s mostly an excuse to give all of these characters friends and/or to establish a sense of normalcy. They are still kids after all. We wouldn’t want every kid running off into a forest looking for a magic tree house to skip school with.

The kids of Mouse Scouts and Dragon Masters I believe are never seen at school. Mouse Scouts focuses on the kids scout group, so it makes sense we don’t see them at school. I believe it is mentioned that they do go to school. Dragon Masters takes place in a medieval kingdom, and the kids are busy training with their dragons to fight evil. The main character Drake is an onion farmer at the start and literally can’t write (though he can read, somehow). No school needed in this setting, though it might be implied that the wizard Griffith teaches them some things in their spare time. Some of the other kids, like Bo, seem more educated. This is likely from their pasts in their homelands, before they became dragon masters.

Sometimes School
Owl Diaries, Clementine, Ivy+Bean, Judy Moody, Stink, Franny K. Stein: Mad Scientist, Isadora Moon, Mirabelle, The Adventures of Sophie Mouse, Marisol Rainey, and Pizazz all feature school as a main focus in many of their books, but not all. We see these kids go to school, but it’s not all they’re about. Most go on adventures outside of school on the weekend. In Clementine’s case, she usually has problems going on that carry between school and home.

Primarily School
Junie B Jones, Captain Underpants, Babymouse: Tales From the Locker, D&D Dungeon Academy, and Mouseford Academy all feature school as a main premise, or the kids are at school enough that it’s a main part of their character. Mouseford Academy and Dungeon Academy take place at schools. Junie and Babymouse are seen at school constantly, and their school friends are main parts of their lives. Captain Underpants sees George and Harold at school much of the time, as their mean Principal Krupp is secretly the heroic Captain Underpants.

Magic

It’s not just for YA wizards! Magic plays a common role in a lot of chapter book series.

Mirabelle series – Isadora’s older cousin Mirabelle is a witch-fairy. Besides dealing with the differences between her parent’s cultures, Mirabelle has a mischievous streak that does more harm than good. She is seen at her witch school a lot, where that mischief tends to cause problems for her stern teacher.

Dragon Masters series – Wizards and magic items feature prominently in this medieval world of dragons. Each kingdom has a wizard. One of the main bad guys is a wizard. Dragons have various magical abilities. Many of the kingdoms have magical artifacts or spellbooks. The list goes on.

Dragon Girls series – The Magic Forest transforms them into dragon girls. Each dragon has a different type of breath weapon. There’s a lot of other magical creatures and items in the forest as well.

Princess Pulverizer: Worse, Worser, Wurst – This specific book features a wizard, though magic items are commonplace in the series. Every deed she finishes, she gets a new magic item. These become very important in her travels in future books.

Magic Tree House series – There’s a tree house that can take you into the past or future. It’s magic.

Supernatural

This is a catch-all for things that aren’t Magic, Unicorns, or Mermaids. There’s enough other weird stuff that it deserves mention.

Desmond Cole, Ghost Patrol series – Ghosts, mermen, and various other creatures are commonplace in this series.

Daisy Dreamer series – The majority of the story takes place in the World of Make-Believe, where imaginary friends of all kinds live.

Franny K. Stein: Mad Scientist series – Franny, as you might imagine, is a mad scientist. Creating supernatural machines and franken-creatures is par for the course.

Superheroes

The other common theme with “Super” in the name. Comics don’t have anything on these heroes!

Captain Awesome series – Eugene’s alter ego Captain Awesome isn’t a traditional superhero, but you don’t need powers to defeat the evils in everyday life.

Pizazz series – Pizazz and her family are all superheroes, because that’s the kind of world this is. Super villains also abound, but everyone in the world isn’t a hero. One of the main points of the story is that Pizazz is one of only two heroes in her class. Because of her unassuming superpower and general unpopularity, being a hero in school isn’t all that.

Captain Underpants series – Harold and George’s principal becomes the goofy Captain Underpants when they snap their fingers. Technically this is hypnotism and he originally has no powers. Later in the series he gains actual superpowers.

Waylon series – Honorable mention. Waylon is the spin-off series to Clementine. He’s another kid in her class. Like Captain Awesome, he also has no powers. One of Waylon’s quirks is that he claims he has a variety of powers, and is always working on developing them. Clem is the only kid in his class that believes him, and even then not most of the time.

Birthdays

And other celebrations. Another common theme that most kids experience in one way or another.

Isadora Moon Has a Birthday – Isadora wants a normal human birthday party, but her vampire dad and fairy mom don’t quite know what that entails. They try their best.

Judy Moody and the Right Royal Tea Party – Judy’s know-it-all sometimes-friend Jessica Finch has a tea party for her birthday. In Jessica Finch in Pig Trouble, she has another birthday. I think Stink has a birthday in Judy’s series somewhere too. Judy’s mom has a birthday in Mrs. Moody and the Birthday Jinx.

Animals

The ones that aren’t Unicorns at least. There’s a big distinction here between series with animals and series with animal characters.

Fictional Animals
Magic Tree House regularly features animals, usually being rescued, preserved, or learned about. Annie’s whole thing is she really likes animals. Later on in the series, she steals the animal portion of Jack’s fact spouting, becoming the de facto animal fact person.

Most series feature animals in extremely minor roles (usually as pets), but I’m not going to list them all here. Digging through hundreds of books for one pet name is a bit much. Off the top of my head, Junie has a dog named Tickle that does nothing ever. Judy has a cat named Mouse and a venus flytrap named Jaws. Her brother Stink has a toad named Toady. Mirabelle has a dragon named Violet. Eugene in Captain Awesome has a dog. Emerald has an octopus. Many of the kids in Owl Diaries (surprisingly) have pets (Eva’s is a bat named Baxter). Clementine has a cat named Moisturizer. Princess Magnolia in The Princess in Black has a horse named Frimblepants.

I think it’d be more interesting to look at the series that don’t feature pets. Maybe another time.

Animal Fiction
Most of the characters in these series are sentient animals, so I’m not going to name them all. Just the important ones. It’s important to note for budding writers that series featuring humanoid animals are mainly for the younger end of the chapter book age group (transitional chapter books).

Sophie and her family are mice, obviously. Her friends Owen and Haddie are a snake and frog. Her teacher is an owl.

The dragons in Dragon Masters are all named and talk. Drake’s Earth Dragon is Worm. Rori’s Fire Dragon is Vulcan. Bo’s Water Dragon is Shu. Ana’s Sun Dragon is Kepri. For all this mythology, I don’t remember many other animal characters besides dragons.

The girls of Dragon Girls turn into dragons. They can still talk. The Magic Forest also features many other sentient (non-human girl) animals. At least I hope those other animals aren’t also kids-turned-animals.

Babymouse is a mouse, shockingly. Her main friend Penny is a poodle. The mean girl Felicia Furrypaws is a cat.

Vacation

Honestly not as many as I’d expect here. I think this might have to do with wanting to stay in one setting. Every time a protagonist goes on vacation, it usually feels very weird to me.

Junie B Jones: Aloha-ha-ha! – Junie’s parents take her to Hawaii, where her antics make things difficult. It’s also mentioned that her rich friend Lucille also has been to Hawaii, because of course she has.

Isadora Moon leaves town a lot, actually. This is the only series that makes it not weird. She goes camping, on field trips, to the beach, also to the beach (but underwater!)

Isadora’s cousin Mirabelle goes to a witch resort, the zoo, her grandparent’s house, and a haunted house.

Babymouse takes a field trip to a big city art museum in School-Tripped. This is probably my favorite book in the series so far. Babymouse and Penny spend the book skipping the museum to find a lost cat’s owner. Penny gets a lot of pagetime. Probably more than she’s gotten in the entirety of the graphic novel series.

The Princess in Black goes to the beach, and then underwater.

Clementine goes on a field trip.

I’m not counting any of the Magic Tree House trips as vacations (even the ones that seem vacation-y). They’re serious history chronicling action.

Sports

Where there’s school, there’s sports. Even sometimes when there’s not school, there’s sports. This is why it has its own category.

Surely Surely Marisol Rainey – Marsiol spends the entire book agonizing over the upcoming kickball game. Will her wish for rain wash out the game or will she be forced to embarrass herself in front of her class again?

Magic Tree House: A Big Day for Baseball – Jack and Annie travel back to 1947 to help out with a historic baseball game.

Captain Awesome Gets a Hole-In-One – Eugene gets invited to the evil Meredith’s birthday party. He battles her at miniature golf to show her who’s boss. Can his alter ego Captain Awesome stop Meredith from cheating her way to victory?

Detectives

A lot of kids like the idea of being a detective. Even in today’s modern world, detectives are still cool.

Thea Stilton series – The globetrotting Thea Sisters solve all kinds of mysteries each book. They do similar things in the Special Editions and graphic novels. Also in Mouseford Academy, just mostly at school. I’m sure I’ll talk about all of these eventually, they’re just really long.

Hardy Boys: Secret Files series – It’s the Hardy Boys. Mystery is their middle name.

Ivy+Bean Take the Case – Bean wants to be a detective like the main character in her mom’s favorite movie. She opens a detective agency and proceeds to not solve the one case she has.

Nancy Drew
I waffled for a while on whether or not I wanted to talk about this point, so I’ll be brief. No I’m not talking about the middle-grade/YA protagonist. Or her other series. Or her other other series. Or her other other other series. Not even her forty book chapter book series (because I haven’t read it). I’m talking about her impact on chapter book series. Both Judy Moody and Nancy Clancy mention the intrepid girl detective a lot. Like a lot a lot. It’s basically an advertisement. The only other time I’ve seen blatant ads in chapter books was when Eugene’s mom showed him a Critter Club book in Captain Awesome.

Judy and her way cooler friend Amy Namey are both fans of Nancy Drew. To the point where they both name drop specific book titles multiple times. I believe they both own full collections of the main series also.

Nancy is also a fan of Nancy Drew, and wants to be a detective like her. This is the premise for the most of the series.

I don’t see the Hardy Boys, Tom Swift, or the Boxcar Children getting this kind of recognition in other series. Just saying.

The New Kid

Usually related to school, but a common enough theme that it needs to be its own thing. Even the titles are almost the same.

Isadora Moon and the New Girl – Isadora has trouble being friends with a girl who doesn’t want to be friends with anyone.

Owl Diaries: Eva and the New Owl – Eva gets upset when the new owl Hailey befriends her best friend Lucy instead.

Captain Awesome and the New Kid – Eugene gets to the bottom of his new classmate Sally. Is she on the side of good, or a harbinger of evil?

The Adventures of Sophie Mouse: A New Friend – Sophie is troubled when she finds out her new classmate is a snake. Can a mouse and snake really be friends?

Judy Moody: Around the World in 8 1/2 Days – Judy meets a new girl in another class who has a lot of things in common with her. Can Judy make a new friend and still keep her old ones?

Weather and Seasons

This one might surprise you. Very common experience, but it can be an excuse for an entire book.

Isadora Moon Makes Winter Magic – Isadora uses her fairy magic to make a snow boy come to life. Snow doesn’t last forever, so will she have to say goodbye to her new friend?

Sophie Mouse has a few weather books, which makes sense for a nature-focused animal series. In Winter’s No Time For Sleep, Sophie and her friends go play in the snow and accidently wake up a sleeping hedgehog. In It’s Raining, It’s Pouring, Sophie’s excitement for the Spring festival is washed out by a rainstorm.

Magic Tree House has a lot of historical weather-related events. Usually natural disasters. Jack and Annie encounter tornadoes, earthquakes, tsunamis, and hurricanes.

Weddings

Another surprising category, this time because it’s directly related to adults.

Judy Moody Predicts the Future – Judy predicts her teacher is in love and finds out he’s getting married for real.

Owl Diaries: A Woodland Wedding – Eva’s teacher is getting married, so Eva and her friends help plan her wedding.

Isadora Moon Goes to a Wedding – Isadora attends her aunt’s wedding and tries to stop Mirabelle from getting up to mischief with the wedding cake.

Conclusions

I’m sure there’s plenty I missed here that get covered a lot. These series get pretty long, so they must stop overlapping topics at some point, right?

A lot of series use their premise for very specific topics. Mouse Scouts goes into scout-related activities, like camping. Jasmine Toguchi deals with topics related to her Japanese heritage and culture. Many just deal with less common, but still relatable activities. Digging for fossils. Trying to be famous. Dealing with rogue mersurfers. As you do.

So I hope this list was helpful, or at least interesting. You don’t have to go far to find a cool topic to talk about. You just have to know how to spin it in a new fashion. Don’t be afraid to tread old ground, there’s still some gems there.