maybe try spending more time with him and never neglect him (not saying that you do). make sure his grades arent slipping, and that he isnt very stressed. dont ask him to do many chores or stressful things like that.  but dont make it to obvious that ur all of a sudden super nice because he will shut down and probably wont want to talk.

If you think your son is cutting himself, seek help immediatly. The best thing to do is get him to a psychatrist or family doctor. Cutting and any form of hurting youself is one of the biggest signs of depression and other mental disorders. Its best to get him to a medical professional who can treat him as to why he feels like cutting himself and if need be provide medication to combat the mental issues.

If you are still unsure try contacting a suicide hotline and asking for advice on how to deal with this or having him do the same if he does not feel comfortable talking to someone he knows about it.

You could also talk to the school counsoler to see if they can provide any resources for you to choose or go to

If your school has counselors, notify them at once. If not see if there are places that you can go that deal with teens and their problems. If you attend church, see if there is someone that is trained in dealing with teens. If you don't have a church, ask friends where there are churches that have trained counselors. Also there is a site on the computer: focus on the family, that can give you printed material and also tell you where you can get help in your area.  Good Luck!

try to get him some help, there is places he can go to talk to someone.
most of all see if he will talk to you and let him know you will be there for him