knowledge of 12 year old boy behavior

I am hoping someone can help me with this situation that has been coming up in our household recently. My husbands son has been having alot of problems. The main problem is at school where he is forgetting alot of assignments which has us concerned seeing that about 3 or 4 of his classes he has F's. He had a few instances at school where he has gotten into trouble. He seems to have a problem remembering things. As for viedo games he does not have a problem remembering those. It frustrates us because we want him to do well and we help with homework and everything but he forgets. We also had another instance where we caught him in lies. One instance lately is that he stole something from the school and it was all on viedotape and he recieved one day in school suspension. We have tried everything as in punishment and taking away things and nothing seems to get through. I guess my question is --is this normal 12 year old boy behavior or is he just testing the waters with us? In the next week or so we will be getting him tested for ADD also. If anyone can give me any info please tell me I will be ever so grateful.
Thanks

[crabby70]

He sounds such much like my nephew...I took care of him till he turned thirteen..He has ADHD...but it could be normal behavior to....Is he in a new school this year...Going into middle school is big change for them...  Best of luck...I have a fourteen year old girl ...she had ADP...she tests the waters almost everyday....best of luck