Request #309 From Jae

I’ve been thinking about this book for ages and no matter how hard I look I haven’t been able to find it and I hope you could help. I read this book somewhere around 2016-18. It was about a girl and her uncle, who was the same age as her, going to this school for gifted students. The school’s district was described as stretching out like an octopus and the children were made to drink smoothies or something while running on treadmills. I want to say it had a yellow cover but I can’t be certai