Look up exercise and depression online it releases endorfins which improve mood and brain chemistry. and Art Therapy; channelling what ur feeling into something creative helps ur brain process the negativity in ur head. also find some volunteer work; helping others or nature builds selfesteem, gives life new meaning gives perspective and good karma... u dont have to believe in god but finding some spirituality can really help and good karma is a good start... basically research all u can on depression then when u find things that help come on here and share with the other deprrssed people, more good karma. Why not join clubs groups and activities outside of school where you ll meet like minded people. Or challenge urself by joining groups u wouldnt normally be interested in. 

Cannibus causes short term memory loss while you are under the influence. Most people who use cannabis don't experience any obvious harmful effects, but regular use may produce a number of short term effects including paranoia, confusion, increased anxiety, and even hallucinations, which can last up to several hours.

Meditation is a proven technique which provides relief from depression/stress/anxiety/sadness and produce happiness. Meditation can be tried as a natural way to overcome depression and to also increase mental strength to face the problems of day to day life.I would recommend you to try mindfulness of breathing meditation and loving kindness meditation techniques. Going on a meditation retreat would help to a great extent. Having been a meditator for the past 4 years I can swear by the results of meditation.