I have a chicken in the same condition as yours. Almost 2 years ago she was attacked by a neighbors dog, and is blind now. Her eyes are there but do not function with vision. I believe she finds her food and water with her sense of smell. She needs special care to be separated from the rest of flock to prevent pecking. I will take care of her until the end. She is 11 years old now. She acts the same as yours , walking in circles sometimes. One way to check her vision is to shine a flashlight into eyes and see if there is a reaction. No reaction with my hen. I am also a realist and in your situation, (school) maybe it would be better to re home her. There is a lot more work involved to taking care of a chicken with needs, like separation from the rest of the chickens.
SORRY TO HEAR such sad stories.
Here are pix how I take care of her.
She probably does not realize that she is in a cage.
This is her before the incident. Looks same now after recovery.
WISHING YOU BEST.