Hi Jason,
To start with, I don't think your I.C.T teacher has the right to simply throw you off a course at school. With your parents help I would contest this with the headmaster. At the same time, with your parents you should get in contact with your local council and ask what they can do to help. Everyone is entitled to an education, and they SHOULD provide you with the means to aquire it one way or another. You may be entitled to benefits, which will allow you to retake your GCSE's at college.
Also, it might interest you to know if you don't already, that 'Codemasters' are based in Southam. They have a careers page here:
Codemasters You can always contact them and ask for some work experience. They may be more than willing to help. Here's their P.O. address. You could send them a letter 'Care of Human resources' or something.
Codemasters, P.O. Box 6
Leamington Spa, Warwickshire, CV47 2ZT
United Kingdom
Hope that's of some help, if not, let me know and I'll think of something else for you to try. I really would get in contact with your local council though, they have a duty to help you.