Talk with your son also about what he wants to do when he graduates. Doing this will build a bond between you so that he knows you want to be involved in his life and that his goals are important to you. Rather than pushing college, help him think about all the ways to implement his career goals. This will show him how a high-school education fits into his future.
It takes many students a while to get their feet on the ground when they first start high school. If your son isn't involved in any school activities, encourage him to take part in some now. Extracurricular activities make school interesting for many students.
Academics become more difficult in high school. Your son may have specific skill deficits that are stopping him from doing well and may need some extra help to bolster his skills.
While your son has no TV or computer games to distract him, is he using this time productively? You need to check that he has done his homework each evening. If you are not sure what his assignments are, it may be possible to check them out on the school's website. Or you can initiate a system with his teachers to find out what his daily assignments are.
In fact, the TV and computer are wonderful tools that can be used to reward your son for completing his homework satisfactorily. Do show him how to use the computer in his homework for doing research as well as making presentations.
