Psychedelics absolutely have an affect on mood. Glowing experiences have left me motivated unusually so for weeks after and difficult one's slightly melancholy for a few days. I took LSD when I was 14 year old child. I think that, in the end, I am glad I experimented with psychedelics at a relatively young age. It gave me an objectivity and mindfulness I wouldn't have had otherwise. I had a troubled adolescence and seem to be better adjusted than my siblings.
However, I had a lot of really self destructive experiences. I would take LSD with no goal and give into manic creativity to a point where it was simply escapism from things like high-school and my physically abusive father.
I also had a friend, who is now diagnosed schizotypal, have multiple violent, naked freakouts in front of me on the same Psychedelics I was taking. I would be lying if I said I don't have PTSD from having to deal with that on three occasions.
It was a mixed bag. I think teens could probably benefit from Psychedlics in a therapeutic setting. It pretty much identical to how some pot smoking in highscool provides a bonding experience for lonely teens while lots of pot can seriously affect acedemic preformance. Enough armchair psychology, just thought I would share my own experience.