When children—grown-ups too, but we’re talking about children here—find characters or worlds they love, they want to revisit them over and over again: thus the power of the series. It’s too easy to dismiss a series: the worldbuilding has been done, the basic character development established—shouldn’t we turn our attentions to something new? But given how important it is for children to keep their feet in the familiar as they stretch their reading muscles, I am happy to have several splendid series books among the Best Books for Middle Graders of 2017.

Perhaps most poignantly, in You’re Amazing, Anna Hibiscus!, the eighth and final story starring Atinuke’s ebullient biracial girl, who has taken readers to her home in “Amazing Africa” and to visit her white Canadian relatives, readers must say goodbye to an old friend. Anna Hibiscus must say goodbye in this story too, as her beloved grandfather passes away. Atinuke and illustrator Lauren Tobia keep the balance between high jinks and heartache pitch-perfect.

Another series book for younger middle graders is See You When I See You, by Rose Lagercrantz, illustrated by Eva Eriksson and translated by Julia Marshall. In this, the fifth book about a little white Swedish girl named Dani, the protagonist is happy to have her widowed father home again after spending the summer in the hospital, but she must cope with the absence of her best friend, who has moved away. The book gently plumbs the very real emotional depths of this second-grader with endless sympathy.

After beginning his Track series last year with Ghost, Jason Reynolds returns with teammate Patina for the second leg of the relay. The ferociously competitive, eponymous black girl “ain’t no junk.” She’s fast, smart, and totally devoted to her family. Readers’ hearts will ache as they watch Patty protect little sister Maddy, negotiate the mostly white school she attends, and share her abundant love among her adoptive parents, Uncle Tony and Momly (Tony’s white wife), and Ma, who’s lost her legs to diabetes and can’t physically take care of her daughters any longer.

With Rise of the Jumbies, Tracey Baptiste takes readers back to Corinne La Mer’s Caribbean island home, which is shaken by an earthquake and then by the disappearances of island children. Corinne makes a deal with Mama D’Leau for help against the mysterious kidnapper. The story deepens the fantastic-adventure plot with an exploration of the legacies of slavery, gently but firmly asking readers to confront it along with her characters.

And white British evacuee Ada returns in The War I Finally Won, by Kimberly Brubaker Bradley. Her club foot has been healed, but the scars of the trauma she suffered at the hands of her unloving mother are still with her. Readers will ache as she struggles determinedly to heal against the backdrop of World War II, which has upended the quiet village in Kent where she lives now, possibly forever.

There are 70 more wise, funny, exciting, and heart-rending books to explore—and here’s hoping next year we will see some more excellent sequels.

Vicky Smith is the children’s & teen editor.