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Hazel's Theory of Evolution

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“Just because you don’t understand it doesn’t make it illogical.”

Hazel knows all about life on Earth. She could tell you anything from what earthworms eat to how fast a turkey can run. That’s because when she’s not hanging out with her best friend, Becca, or helping care for the goats on her family’s farm, she loves reading through dusty old encyclopedias. But even Hazel doesn’t have answers for the questions awaiting her as she enters eighth grade.

Due to redistricting, she has to attend a new school where she worries no one will understand her. And at home things get worse when she discovers one of her moms is pregnant. Hazel can’t wait to be a big sister, but her mom has already miscarried twice. Hazel fears it might happen again.

As Hazel struggles through the next few months, she’ll grow to realize that if the answers to life’s most important questions can’t be found in a book, she’ll have to find them within herself.

352 pages, ebook

First published October 8, 2019

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About the author

Lisa Jenn Bigelow

4 books188 followers
Michigan native Lisa Jenn Bigelow is the critically acclaimed author of the middle grade novels Hazel’s Theory of Evolution (2019), winner of the 2020 Lambda Literary Award for LGBTQ Children's/Middle Grade, and Drum Roll, Please (2018),  an Illinois Reads selection and Michigan Notable Book; and the young adult novel Starting from Here (2012), an ALA Rainbow List Top Ten Book. A graduate of Carnegie Mellon University and the University of Illinois at Urbana-Champaign, she serves as a youth librarian in the Chicago suburbs during her non-writing hours.

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5 stars
448 (46%)
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387 (39%)
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116 (11%)
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14 (1%)
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Displaying 1 - 30 of 230 reviews
Profile Image for Kathleen.
Author 1 book47 followers
August 6, 2019
There's one section towards the end, where Mimi's talking to Hazel, and it's everything I wish I'd been told when I was Hazel's age, that it's okay not to want a romantic relationship or a sexual relationship, that all the stupid heteronormative milestones and relationship expectations aren't actually requirements and it's okay to want something else, or only parts of them.
Profile Image for Anniek.
1,761 reviews648 followers
May 17, 2020
This book was very different from what I expected, but it was also very good. It's mainly about one of Hazel's mums being pregnant again after two miscarriages, and Hazel having a hard time dealing with her anxiety surrounding this pregnancy. At the same time, Hazel is starting at a new school and feels her best friend drift away from her when she becomes friends with Hazel's former bully. She learns that there's always room for hope in any situation, and that you can always make room for new friends.

I loved reading about this baby ace so much. This part of the storyline was more of a side plot than the actual focus, but that's okay, because it was lovely, it inspired a wonderful chat with one of the Hazel's mums, and we need different types of representation anyway. It was just so wonderful to see this represented in a middlegrade novel!

Rep: questioning aromantic & asexual MC, sapphic mums, one of which is black, trans Latinx side character, disabled Asian side character, Jewish side character

CWs: miscarriage, ambulance, hospital, bullying, mention of suicidal thoughts
Profile Image for Andy.
2,408 reviews190 followers
December 2, 2021
Thank you to Harper Collins & HarperKids for sending me a finished copy in exchange for an honest review and promotion. All opinions are my own.

Can we please have more middle grade contemps like this!? To see a middle grade book like this that's just so inclusive makes me cry for middle school me who didn't have anything like this. I'm so happy future generations will.

This book centers on young Hazel who has been moved to a new school thanks to new districting guidelines. While at this new school Hazel has a hard time trying to make friends while also staying connected to her best friend from her old school. Things are only made more complicated for Hazel when her mom, Mimi, tells her she's pregnant again. Hazel is unsure of how to balance and cope with all the worries and anxieties.

I loved this book so much. My only gripe is that we don't get to see Hazel use the words aromantic or asexual in terms of her identity or even know that they exist. I really wish the health class mentioned it when they got to their sexuality lesson.

Hazel is such a strong and intelligent young girl. I wish I had more younger characters like her when I was growing up. I related a lot to Hazel and I loved how much she loves animals. There are so many great animal facts in here and it made for such a fun aspect of the book.

Rep: white questioning aroace female MC, MC has two moms (one white, one Black), Latine trans female side character, Asian male side character in a wheelchair, Jewish female side character, Black trans male side character (brief mention).

CWs: Bullying (mostly past mentions), grief, infertility, past miscarriages, pregnancy. Moderate: Acephobia/acemisia.
Profile Image for Nev.
1,051 reviews135 followers
January 18, 2020
For the majority of this book I was feeling like this was a 3 or 3.5 star read. There definitely wasn’t anything wrong with it, but I also wasn’t totally engrossed by the story. Hazel has to move to a different school and ends up drifting away from her only friend while also dealing with the stress of one of her moms being pregnant. But damn, those last 50 pages just hit me in a way I wasn’t expecting and had me SOBBING.

I liked how casually queer this Middle Grade book was. Hazel has two moms and one of her friends is trans. And while the words aren’t used within the story, Hazel is portrayed as ace/aro. Something I wasn’t really aware of was how much this book would deal with Hazel’s complicated feelings around her mom’s pregnancy. Mimi previously had two miscarriages and there’s a lot of discussion around that and how it impacted the whole family.

I don’t think this was the perfect Middle Grade book. Sometimes it would spend too much time explaining concepts or random things that really weren’t that important to the plot of the book. I felt like occasionally the story would get bogged down by all these random asides. But overall this is a really sweet book. And it made me cry more than anything I’ve read recently… But that also could’ve been because I’d had a couple drinks before reading the end 😅
Profile Image for Kathie.
Author 2 books66 followers
May 25, 2019
Thank you to the author and HarperCollins for an ARC of this book.

Can I just say that I consider Lisa Jenn Bigelow one of the most underrated middle grade writers whose books I've had the pleasure to read? Last year, her book DRUM ROLL, PLEASE was one of my favorite reads of the year, and now HAZEL'S THEORY OF EVOLUTION has also captured my heart. I sincerely hope you'll add this book to your TBR list to when it's released on October 8th.

Due to school zone restructuring, Hazel is forced to go to a new school for her last year of middle school. She just wants to be invisible and make it through the year so she can be with her best friend, Becca again, but life has other plans for Hazel. She's befriended by Carina, a student from her former school who is looking for a new start. She also develops a "sort-of" friendship with Yosh, and the three kids become their own group who feel like they don't quite belong, but somehow fit together. But things at home are really hard for Hazel when she discovers one of her moms is pregnant after two previous miscarriages, and she tries to figure out what it means to her to be a sister.

There are many issues being quietly explored in this book. It looks at infant sibling loss, and the impact it has on family members. It addresses sexuality, and includes a transgender character who is an important part of the story, but whose sexuality is not the main focus. It also addresses disability, and I love that the characters from a wide range of life experiences bring their diversity to the story in supporting roles. It's a character-driven book, and succeeds in drawing the reader into their lives.

I look forward to reading more from this author, and hope you'll add her books to your TBR lists.
Profile Image for Nessa [October Tune].
639 reviews63 followers
November 5, 2021
This was such a fast read, I couldn't put it down. I loved Hazel and her family so so much.
Profile Image for Kerry (lines i underline).
502 reviews161 followers
June 20, 2021
4.0⭐️ “There are so many good ways to be in this world.”

This beautiful message encapsulates a lot of what this book is all about. I haven’t read a Middle Grade novel that offers representation in so many ways, without it seeming at all effort full or done to check boxes. This is a book that will give many young readers a feeling of being seen in literature, perhaps for the first time, and that is so important. I hope teachers, librarians and booksellers find ways to get it into the hands of kids who need it most.

I haven’t ever read a book for children where miscarriage and it’s aftermath was so much a part of the story. It is presented in a nuanced, honest way. Perhaps this will be the first time many young readers will even think about this experience, and this book would be a sensitive introduction to this difficult topic.

Loved the family dynamic here, and also the friendships Hazel cultivates. They are complex and imperfect and loving and true.

Hazel is sometimes pretty aggravating, but I suppose that makes her a typical middle schooler. I did find she seemed young for eighth grade. She struck me more as a sixth grader. This would be more of a book to put in the hands of a mature fifth or sixth grader than the average eighth grader I think.

It’s a quiet read, so not all kids will find that appealing, but no book is made for all kids.

A lovely read about how change comes to our lives, whether we are ready or not, and growing through it.

CW: miscarriage, grief, bullying, death
Profile Image for Laura.
430 reviews5 followers
November 11, 2019
Honestly this might be the best book I've ever read, and I'm not even the intended audience.

The book follows 13 year old Hazel who is starting her 8th grade year at a new school, thanks to district rezoning. Hazel is 13, with frizzy hair, glasses and lives on a farm in Michigan and to be honest I was pretty sure this was my literal exact childhood. Introverted, loves to read and spend time outside? The biggest difference is that my farm had Pumpkins instead of goats haha.

Anyway, This is a particularly hard year for Hazel. One of her moms is pregnant, after suffering two miscarriages, shes starting this new school and shes afraid she'll lose her best friend in the process.

The story is wholesome, relevant, and just feels true. I literally was crying in the last quarter of the book, something that is really really rare for me. I really felt for Hazel throughout the story, and it really reminded me of how difficult navigating middle school is without the additional worries Hazel had going on. Life is confusing and hard at that time and Bigelow tackles it perfectly.

The story has a diverse cast, and covers some really heavy topics for a middle grade book but does so in a way that feels organic and age appropriate.

I have nothing but love for this book and intend to check out more of Bigelow's work after this.
Profile Image for Shaye Miller.
1,236 reviews81 followers
December 26, 2019
You know what? This book was way more EVERYTHING than I expected. I realize it is classified as middle grade literature, but I would say it’s intended for older middle graders as well as the YA crowd. There’s just a little language (ex: damn) and some younger kids may be all giggly in a class read aloud where the word “teets” keeps being mentioned (because they live on a goat farm where goats are milked regularly). One of Hazel’s moms has experiences two miscarriages and so there’s a lot of fear and uncertainty when the family discovers she’s pregnant again near the beginning of the book. I don’t want to say too much about the storyline, but Hazel is figuring out who her friends really are while also discovering what it is to be a good friend to someone new. The story has Jewish, transgender, and queer rep AND Hazel loves science, so there’s a lot of STEM strewn throughout. This may be my final 5-star rating for 2019 — really enjoyed it!

For more children's literature, middle grade literature, and YA literature reviews, feel free to visit my personal blog at The Miller Memo!

Right after I finished reading:
So much deeper than I ever anticipated. REALLY great story, writing, and resolution. Can't wait to share more on Monday!
Profile Image for Kathy.
Author 1 book220 followers
April 3, 2023
CW: for discussions of multiple miscarriage, grief, bullying, medical emergencies, blood.

I'm glad I was in the safety of my hotel room while listening to the last portion of this audiobook, because it had me sobbing. There's something about young folks dealing with multiple forms of stress at the same time that just breaks me. This was a fantastic story of family, friendship, and self discovery.
Profile Image for Melissa.
164 reviews42 followers
December 12, 2022
As I've seen time and time again: QUEER MIDDLE GRADE HOLDS MY HEART. There's something so special about reading something meant for kids, meant to help them understand themselves and those around them. It's so beautiful.

I think my favorite part of this story was hearing Hazel's voice. I loved listening to her talk about what she was passionate about (go worms!!) and seeing this small glimpse into a life that is there for her. And watching her struggle with the very adult issues that were happening with her family — a new pregnancy after two late-term miscarriages — was honestly refreshing. Because she took us back to what it feels like when everything is out of your control and you feel like you should know how to change that.

It's such an innate need to know that drives Hazel, and that was incredibly endearing and relatable. She took me back to moments of my childhood asking question after question, right as they popped into my head.

Hazel's Theory of Evolution is a beautiful story and an important read with a message and perspective that speaks to anyone regardless of age. It makes me so happy that there are special books like this in the world.
Profile Image for Emily.
451 reviews48 followers
April 25, 2021
Esse livro me deu tudo que eu queria sem nem precisar pedir: uma protagonista aro ace, uma personagem trans, duas mães, um personagem pcd, um irmão mais velho muito carinhoso, CABRAS e mais um tanto de coisa. Eu gosto muito como a Lisa Jenn Bigelow consegue lidar com vários temas difíceis de uma só vez, sem minimizar nada ou deixar a leitura cansativa. A Hazel precisa lidar com a nova escola, a melhor amiga mudando o rumo da vida e deixando ela pra trás (SERÁ HEIN HAZEL), a gravidez da mãe e o medo avassalador de que ela perca o bebê – pela terceira vez. Mais pro final, a Mimi e a Hazel têm uma conversa sobre não precisar querer um parceiro romântico ou sexual e que a gente não precisa seguir os padrões impostos pra gente que me deixou chorando igual um bebê – e isso é só outra coisa que a Lisa faz muito bem, criar personagens complexos e cheios de vida (eu queria MUITO uma fanfic sobre as mães da Hazel se apaixonando lmao) que fazem muito sentido. Lisa Jenn Bigelow se você quiser a LUA eu vou lá te buscar.
Profile Image for elise (the petite punk).
403 reviews118 followers
December 29, 2021
4.5 stars

This was so wonderful for so many reasons. Any books about the struggles of being in middle school—friends, fitting in, deciding what you’re now too old for and what you’re still too young for—will always have a special place in my heart.
Profile Image for Camille.
130 reviews51 followers
February 28, 2021
Aro-ace main character who has 2 mothers, disabled kid rep and trans kid rep, and just for this, it deserves all the stars.

I've never read something so heavily focused on miscarriages, and the impact it had not only on the parents, but on the siblings as well, and while it can be a difficult topic, I found it well done.

Even though the terms are and ace aren't used in the book, the signs were here. I was able to see them because I'm familiar with them, but the author's note at the end was very welcome.

I'm glad kids have access to books like this now, and I wish I had when I was younger.
Profile Image for Nadja.
1,563 reviews62 followers
October 6, 2020
"This book doesn’t focus on the fact that there are people who are gay, black, Jewish, ace+aro, or in a wheelchair, they’re just people. And the fact that this exists so easily makes my heart so very, very happy." perfectly said by Star.

MAMMAMIATHON 2020: Donna, the winnter takes it all, read a book that has won a prize/award.

Becca’s Bookoplathon Sept. 2020: Set in the Present.
Profile Image for Eloise.
593 reviews238 followers
November 6, 2019
Well this was a delight.

Hazel is the sweetest 14 year old you'll ever read about. She loves her science books, her animals, her friends and her family so much my heart explodes just thinking about it. She's full of wonder, cheerfulness but also feeling like the odd one out.
Her relationships with new friends, old friends, her family and her animals were all so realistic and imperfect but beautiful.
And of course, she spends a lot of time questioning the meaning of love, with regards to friends and family. Can you love someone who was never even born? Can you love your family when they're doing scary things that might hurt them? Can you love your best friend who seems to be turning against you..? Her thoughts and feelings are very touching and so relatable in ways i have rarely seen in books i've read.
So thank you, Lisa Jenn Bigelow. I cannot wait to read more from this author.

Also, two mums and a trans friend who were simply part of the story without making a big deal out of their identities : Perfect.
Profile Image for emmy.
442 reviews
November 19, 2019
This book is a delightfully queer middle grade novel about a relatable and sweet feminine protagonist, with some neurodivergent qualities. I will handsell this, and particularly recommend it for classrooms.
Profile Image for Kate.
Author 15 books822 followers
August 6, 2021
When Hazel is forced to start at a new school due to redistricting, she plans to lay low so as not to become "Goat Girl" - the mean nickname from her old school. She tries to hold onto her old best friend Becca, but Becca's suddenly interested in cheerleading, and she isn't sure about her two new friends, so when one of her moms tells her that she's pregnant, Hazel feels like she can't tell anyone. Her mom has had two miscarriages before and Hazel worries that this pregnancy will turn out the same.

I identified with Hazel so much in this story - getting me to talk about my emotions is like pulling teeth and each time Hazel had the opportunity she did exactly what I would do. The word "asexual" is not used during the story, not until the afterword, which I kinda loved because sometimes labelling yourself limits you, and it was pretty obvious to me that Hazel was ace but this also gave her time to decide. Hazel's life on the farm was quirky in a quiet way, and she reminded me a lot of homeschooled kids who have a very different outlook on things (in Hazel's case, she likes creatures like skunks, earthworms, and cockroaches). The friendship drama with Becca was realistic and highlighted the difference between kids who are allowed cell phones and social media accounts and those who aren't and how difficult it is to connect. Overall a heartwarming story perfect for tweens going through that awkward middle school stage.
Profile Image for Ris Sasaki.
914 reviews162 followers
June 19, 2021
2.5 ⭐

Even though I enjoyed my time reading it and enjoyed the way that the author introduced and handled certain topics and situations (as abortions, discovering your own sexuality, acceptance to who you are and acceptance and love towards queer people), I must say that overall I found this book to be quite... okay.

Nothing special and nothing new to add to the whole book community.
I think this would be a good book to introduce a child to read LGBTQA+ books or if you're an adult that want to start to read queer middle grade, this is a good start point, but after you've been on a stride reading book after book on the same genre, things dont hit the same anymore...
Profile Image for Sonia.
Author 1 book49 followers
April 26, 2021
This book packs a hell of a punch for a middle grade with an adorable cover! I for sure felt Hazel's grief over losing friends and her mom's miscarriages, and just generally that middle school awfulness where everything is awkward and raw and confusing. Also, excellent goat content.
This entire review has been hidden because of spoilers.
Profile Image for Laura.
616 reviews25 followers
March 28, 2022
4.5 stars

This was so sweet! There is a lot going on here, so the ace/aro stuff is done with an extremely light touch, almost blink-and-you-miss-it. But overall this exploration of family, grief, love, and identity is really lovely.
Profile Image for Mikayla Tewksbury.
122 reviews5 followers
July 21, 2019
This is one of the most heartwarming middle grade books I've ever read.

Hazel has a lot going on: keeping up with the family farm, surviving the eighth grade at a new school because of redistricting, and now to top it off: one of her moms is pregnant again after having two miscarriages. Navigating the next few months will be more challenging than milking the goats on her farm, but Hazel will learn about herself along the way and form new relationships.

This coming of age story is perfect for new generations navigating the world, and I highly recommend it.
Profile Image for Shan Salter.
80 reviews13 followers
April 14, 2019
Thanks to the @kidlitexchange network for the review copy of this book. All opinions are my own.

Hazel’s Theory of Evolution by Lisa Jenn Bigelow

Release date: 10/8/19

From the author of DRUM ROLL, PLEASE comes this quiet, character-driven, middle-grade novel overflowing with heart and raw emotion.

Introverted eighth-grader, Hazel, lives a peaceful life on a goat farm with her animal books, two moms, and her older brother. Her life takes an unwelcome turn when the school districts are redrawn and she finds herself in a new school without her best (and only) friend. On top of which, one of her moms becomes pregnant after two past miscarriages - a prospect which terrifies Hazel.

As the story unfolds, our heroine struggles internally and even experiments with ‘hiberbating’ her emotions in order to protect herself from the perceived threats of heartache in her life. Luckily, two new friends (a kind transgender girl and an outspoken wheelchair-bound boy) weave their way in at just the right moment: providing Hazel with some much needed humor, distraction, and kinship.

Hazel is the worrier in all of us and reader’s are sure to fall in love with her from the moment she discusses the importance of earthworms in Human Development class. Her journey of inner growth and self discovery is both empowering and believable. The handling of sensitive topics such as infant loss, sexuality, identity, and disability are expertly handled thanks to the first-person narration and Bigelow’s mastery of character-driven story telling. This book is not to be missed!
Displaying 1 - 30 of 230 reviews

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