What reading level is Things we know by heart?

Things we know by heart by Jessi Kirby is at a Level 5-6 reading level (Lexile 840L). Recommended for Middle Grades readers (Ages 9-12).

What age is Things we know by heart appropriate for?

Things we know by heart is recommended for Ages 9-12. HootRating: 10ME (Moderate — Emotional). Content flags: Loss & Grief, Fear & Anxiety, Emotional.

What genre is Things we know by heart?

Things we know by heart is fiction — Young Adult Fiction.

Does Things we know by heart have any content warnings?

Things we know by heart has a HootRating of 10ME (Moderate — Emotional). Content flags include: Loss & Grief, Fear & Anxiety, Emotional. On HootRated, every book is rated across four dimensions — emotional, physical, social, and thematic — to help parents make informed choices.

How many pages is Things we know by heart?

Things we know by heart by Jessi Kirby is 291 pages.

Reviewed by HootRated editorial · Last updated May 18, 2026

Things we know by heart

Jessi Kirby

Things we know by heart

Age Rating, Reading Level & Content Guide

by Jessi Kirby

Reading Level 5-6 10ME Ages 9-12 Matched

The text is written at a 5th grade reading level, the subject matter is intended for middle graders (ages 9–12), and the content has moderate intensity with some emotionally heavy themes.

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About This Book

Have you ever wondered if a part of someone you love could live on inside someone else? Quinn’s world changes forever when her boyfriend’s heart is donated to a stranger. What happens when she meets the person carrying that heart—and feelings she never expected?

Themes

GriefLoveHeart TransplantationComing of Age Family

Quick Assessment

This middle-grade novel explores themes of grief, love, and organ transplantation through the story of Quinn, who seeks connection and closure after her boyfriend's death by reaching out to his organ recipients. It thoughtfully addresses emotional loss and healing, making it suitable for readers aged 9-12. Parents should note the story involves complex feelings around death and identity but handles these topics with sensitivity.

Why we rated Things we know by heart 10ME

Things we know by heart is written at a Level 5-6 reading level with a Lexile measure of 840L across 291 pages. Strong independent readers around grade 6.5 can typically handle this book on their own; with parent or teacher support, Things we know by heart works for readers up to grade 7.5.

We rate Things we know by heart as 10ME ("Moderate — Emotional") because the content sits in the "Moderate" range — moderate conflict that may involve loss, scary scenes, or interpersonal stakes. The strongest signals come from emotional weight — these are the dimensions parents should evaluate against their reader's tolerance.

Specific content flags noted by reviewers: Loss & Grief, Fear & Anxiety, Emotional.

Thematically, Things we know by heart explores grief, love, heart transplantation, coming of age, and family — these threads give the book room to mean different things to different readers. Each of these themes is concrete enough to seed a real conversation, not just a moral lesson.

Good fit for

✓ Children in the Ages 9-12 range — the maturity and attention span match the story's pacing.
✓ Patient readers who enjoy slower, character-driven stories.
✓ Readers ready to talk through themes after they finish — there's enough substance for a meaningful conversation.
✓ Kids drawn to stories about grief, love, heart transplantation.

Maybe not for

! Readers who get easily upset by emotional or moderately dark scenes — the conflict here is real, not just background flavor.
! Children currently coping with grief — the themes may hit close to home.
! Reluctant readers who need a fast hook — the pacing here rewards patience.