My 11 year old son Brady

[sidetrak17]

Ever since I separated from my boys' father a little over 7 years ago, my oldest son's personality has drastically changed.  This once happy, smiling, boy who was like a sponge when it came to learning about anything that was around him, has turned into a brooding, angry, moody pessimist who just screamed at me today (first time ever)...I HATE YOU!!  This was in response to me being upset that he brought home an F in Math!  We had done extra practice work, I tried helping him to understand concepts he didn't get at first, homework was completed on time with my supervision, and the boy for some reason made a conscious choice to fail to turn in the completed homework!  His teacher's comments were: Lack of effort and Fails to turn in homework.  Not just one teacher either, two of them.  My son could easily make straight A's with minimal effort, and this is the second time in his short school career he's done this.  He almost failed 2nd grade for this very reason, yet was 1 point away from the score for gifted student programs!  Friday I have a Doctor's appointment to get some advice.   HELP!!!!!!!!!