YA novel that was published in 2019 or before 2019. I know one of the main characters names is Summer.

[dania 🌷]

i belive she got killed? there was a friend group made up of 3 girls. one of their teachers killed summer. i know at the beginning of the book there was some cult like shit with rocks in a circle in a forest or something.

[dania 🌷]

i read the book when i was in 7th grade (i am now in 12th grade)

[Ellie]

This is almost definitely Broken Things.