I'm telling you he's a tough cookie to crack. Nothing short of anything seems to work. But honestly, I can't say he's a "bad" kid because he's not. He's home most of the time and not out rising hell in the streets, otherwise, I really don't know what I'd do. He just needs some real motivation, spark, something that will get him GOING.
I feel for you. This is my son, except 13yo. He doesn't like school either. We've tried homeschool. public school and now private school.
The consequences thing does work, it's just hard to see your child deal with them. We want to rescue them. In our house, it's a huge conflict because daddy keeps bouncing between rescuing DS and nagging him. Both are owning DS's responsibilities. The result is, DS won't own anything but Minecraft
I've told him that legally, we are required to feed him, clothe him, make sure he gets to school and give him a place to sleep. All else is a gift from us to him.
We've gone over how much it will take him to pay us back for failed classes working minimum wage. He may end up working a job that he hates, but that's because he's making choices now that will limit what choices he will have in the future.
I've also told him that now that he wouldn't be in the youngest grade in middle school, if he chooses to fail classes we're paying for, I'll transfer him to his assigned MS. They have huge discipline problems and it would break my heart but I don't want to raise an entitled child. I'm M to one, TYVM. I'm raising a man, not a child.
Check out some of the info at http://www.loveandlogic.com/ for some ideas. Most may be geared towards little kids, but it's never too late to start the consequences and problem solving.
I really feel for you, because what I quoted above can be DS. It's frustrating to have the good but totally unmotivated kid. You have to find the motivation. Maybe it's having him do more work to make up for what he doesn't do. For instance, when my kids have forgotten something at home (like lunch), I have been a SAHM and we live less than 3 miles from the school. I can take them their lunch, but then they have to pay me back for my time by doing some of my chores.