Failing a final exam

Brooke, my son failed his final math exam for the second year in a row. He says that it was the hardest exam he has ever written and claimed the teacher did not teach them all the concepts that were on it. I am struggling because he still does not acknowledge he is part of the problem and his success is completely out of my control. He doesn’t listen to us and refuses help.

Unintentional model
C- son got a 34% on his final
T- He doesn’t care and continues to blame anything and everything outside of him.
F- frustrated
A- I made the mistake of pointing out that he still hasn’t grasped that more effort is needed.
R- he refuses to talk.

I can’t even think of an intentional model because I feel like I’m failing as a parent. I’m scared of him and terrified to say no. Which is probably the root of the problem for me. Can you point me in the direction of what I need to do…