I am in the very same situation myself.
I go to high school (videregående) as well, and because of stress related to school, I am dropping some subjects this year just to complete them a year later than the average person would have spent. In other words, instead of a three-year-highscool, which is normal, I am spending four years instead. This helps a lot, and I can personally relate to your issues.
However, I would gently recommend you to not being so rude when replying to answers you are given in this thread. It will make you sound desperate and unwillingly to change your pattern, which will make you stuck where you are at the moment. Doesn’t sound very tempting, does it?
I get very bad grades myself. It is not, however, caused by a lack of intelligence, but instead I simply do not find the required motivation to accomplish my goals within school. This in turn makes me unwilling to concentrate and focus on school work, which is being reflected upon my test results. All in all, I am doing very bad. Last year I failed one subject (Spanish).
I am by no means attempting to hijack your thread, however I am trying to express my sympathy because I know exactly what you are going through. The problem does rely on your thought pattern. This is indeed a undeniable fact unless you have some other undiagnosed learning disorder.
Speak with people, if you manage, about anything. You will most likely recieve required help from a shrink or anyone else who can relate to your problems. I am aware this might sound like a cliché, but do not give up: If you do, you will be stuck where you are.
Good luck.
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