Shark teeth / Sherri Winston.

Enhanced descriptions from Syndetics:

From National Book Award longlisted author Sherri Winston comes an important middle grade novel about a girl's tumultuous journey to keep her family together, even when she's falling apart.

Sharkita "Kita" Hayes is always waiting.
Waiting for her mama to mess up.
Waiting for social services to be called again.
Waiting for her and her siblings to be separated.
Waiting for her worst fear to come true.

But Mama promises things are different now. She's got a good job, she's stopped drinking, stopped going out every night-it's almost enough to make Kita believe her this time. But even as Kita's life is going good, she can't shake the feeling that everything could go up in flames at any moment. When her assistant principal and trusted dance coach starts asking questions about her home life, Kita is more determined than ever to keep up appearances and make sure her family stays together-even if it means falling apart herself.

As the threat of her family being separated again circles like a shark in the water, the pressure starts to get to Kita. But could it be that Kita's worst fear is actually the best thing that could happen to her family . . . and to her?