should i stay in high school or should i go to job corps? im failing four classes should i just make em up & keep going?

The reason why you are failing 4 classes will also get in the way of anything else you attempt. First figure out why you're failing those classes. If you don't understand the material, seek assistance. If you just don't like the classes, you need to learn responsibility and consistency. If you lack either of those qualities, you won't do well in job corp or any other thing you attempt. Show yourself you can pass those classes, and the process of doing that very thing will make you far more ready to take the next step!

the best option is to finish high school and get a diploma; even if that involved retaking classes that you failed. a GED is not as well accepted as a diploma is; and actually, an associate's degree or a bachelor's degree from an accredited college or university is better.