Psychologically, depression is guided by inner beliefs that get shaped during key periods of development. 
Socially, depression becomes intertwined with social roles. 
Spiritually, depression is affected by a sense of meaning and purpose in the world. 

1.     Lighten up.

Laughter is often the best medicine for the high school years. One of the best strategies for de-stressing the whole family is to try not to take everything too seriously. Laugh with your teen, and have fun. 

"I wonder what these people assume when they catch a little glimpse of each other, or of me. I wonder if they make judgments on each others’ intelligence, morality, income, or religious affiliation." 

So I’m sorry kids. I have heard your arguments, and I have analyzed your so-called evidence. No, I don’t agree that your daily use of weed is “no big deal.”