The link listed above addresses the multifaceted complex nature of suicide. The link above, attempts to address factors as to why teens think about suicide, the impact of depression, substance abuse, and possible warning signs. The other great points mentioned on the site provide insight about taking a realistic approach about being a teenager and (healthy) coping when possible self-harm thoughts occur.
Although this is a very delicate and sensitive topic here are number of other topic this site also provide information about:
Am I in a Healthy Relationship?
Post-traumatic Stress Disorder
Death and Grief
Getting Help for Intense Grief
Going to a Therapist
Stress & Coping Center
When Depression Is Severe
Why Do People Get Depressed?
Finding Low-Cost Mental Health Care
My Friend Is Talking About Suicide. What Should I Do?
5 Ways to Help Yourself Through Depression