SOLVED. Girl with abusive mother, scared of ferris wheels, dad dating a photographer [s]

[Rachel]

The girl is an only child who lives with her mother who does things like hold her head under the water if she puts too much water in the bathtub. She sometimes goes out with her dad, who is unaware of the abuse and there's a scene where they go to a Coney Island type place and meet the dad's new girlfriend who is one of those people that takes your picture then tries to sell it to you. She is scared of the ferris wheel, because she says it "grabs you and throws you" and this description, I think is what makes a school counselor or someone wonder about her.
I read this book in the 80s. Probably a middle grade book.

[Rachel]

Found it! It's The Girl Who Lived on the Ferris Wheel, by Louise Moeri

[Rainbowheart]

The Girl Who Lived on the Ferris Wheel for the link.