I've been considering suicide?

[Hannah]

Have you already told your teachers, the school director or anybody at your school who holds a position of power about your bullies?
You might be thinking that complaining about it to your superiors would make you weak, immature or anything like that, but it certainly does not. Life is a wonderful thing when it is lived to the fullest, and so if these kids are a hindrance to your full enjoyment of life it is fully understandable and in no way childish to take the appropriate measures so as to bring back happiness into your life.

Yes, it can be perceived as a sign of weakness to not solve everything by yourself, but so what? What's the point of wasting precious time of your life that you're never getting back trying to be super strong by standing alone and suffering when it all turns out to be so hard for you to bear when you can just let others help you and savour your life? We all have our weaknesses. And there's nothing wrong with that. Seek help, talk about your feelings to the school counselor or any other therapist.
You might think there's nothing they'll be able to do about it, but you won't know that until you'll have actually seen one. It's their job, so have some trust in their ability to do what they've studied and are getting paid for.

If you don't perceive yourself as weak, but are scared of your bullies viewing you as such and thus viewing you as an easy target, I think you are to take more account of the fact that most people aren't 100% bad (or good), if they were to know that they're making you suffer to the point you're now struggling with suicidal thoughts, it might confront them with their horrible behavior, make them realize that they are actually KILLING you and stop. This applies to your brother too. Have you ever had a serious talk with all of them about your feelings?

If you think these guys are so heartless that they wouldn't budge despite knowing how you truly feel, maybe you should focus yourself more on changing YOUR behavior instead of theirs. Why do you let them get to you?
You wouldn't believe the mentally challenged man who calls you a zebra because, firstly, the fact that he's mentally ill would discredit him and make him an unreliable source of self-knowledge to you and secondly, even if he weren't ill, you wouldn't believe him since it'd be so obvious with one glance at yourself that you are no freaking bush animal.
Likewise, the fact that they are jerks and are purposully seeking to destroy you skews the vision they have of you and makes them treat you with bias, which means you shouldn't consider them a reliable source either and let what they do and say affect your self-esteem and self-image that much. You should instead have the self-confidence to look at yourself and just KNOW that they are talking nonesense when telling you you're stupid and brush it off.
YOU have the choice, the power to let some things affect you or not.

Don't try to lift yourself up by putting others down, which you seem to be trying to do when wanting to be able to tell yourself that Conor "isn't going anywhere". He is going somewhere, but this shouldn't matter to you. No need for jealousy or whatever, just let him live his life without caring and expect him to let you be too. Likewise, stop comparing yourself to your brother. Maybe he is better than you in many things, but so what? Good for him. Life is NOT a competition, so live at YOUR own pace. Not your brother's or Conor's. YOUR.

That means you've gotta accept yourself, your strengths and weaknesses and the fact that you can't do more than your best. Work with what you've got. Maybe you fail not because you can't succeed, but rather because you aren't doing things the right way. Maybe you're using a studying method that works for others but doesn't suit you (hence the insufficient marks) and should look for another one. Embrace your uniqueness.
Those, too, are things you should discuss with the school counselor.

Some people have wanted to live, but couldn't because of illness, poverty, etc. You have the chance to be able to live however, so instead of considering the permanent solution to a temporary problem that is suicide, seek productive solutions. Solutions that will make you able to relish the delicious gift that life is.

With that said, I'm wishing you tons of good luck and strength in the future!