Just shy of ordinary / A.J. Sass.

Enhanced descriptions from Syndetics:

In this heartfelt novel about family, friendship, and identity perfect for fans of The List of Things That Will Not Change and Ivy Aberdeen's Letter to the World , a thirteen-year-old nonbinary kid discovers that life doesn't always go according to plan--especially when they start public school for the first time. ​

Thirteen-year-old Shai is an expert problem-solver. There's never been something they couldn't research and figure out on their own. But there's one thing Shai hasn't been able to logic their way through: picking at the hair on their arms.

Ever since their mom lost her job, the two had to move in with family friends, and the world went into pandemic lockdown, Shai's been unable to control their picking. Now, as the difficult times recede and everyone begins to discover their "new normal," Shai's hoping the stress that caused their picking will end, too.

After reading that a routine can reduce anxiety, Shai makes a plan to create a brand new normal for themself that includes going to public school. But when their academic evaluation places them into 9th grade instead of 8th, it sets off a chain of events that veer off the path Shai had prepared for, encouraging Shai to learn how to accept life's twists and turns, especially when you can't plan for them.