Young people often have very little control over their lives and this can be an element to stress, depression and anxiety. Young people are vulnerable to peer pressure, bullying, sexual abuse and rape and many other factors - very little surprise, then, that they have PTSD, dissociation, self harm, emotional regulation problems, anxiety, depression, suicidal ideation. The stats are shocking. 1 in 4 for mental health (tho this is over course of lifetime), estimated between 1 in 4 and 1in 6 girls will experience sexual abuse/rape by age 18. Between 1 in 6 and 1 in 10 boys will also experience sexual abuse/rape. Of those stats the majority of the available data says it will happen before puberty (tho personally I think that many young people don't recognise peer to peer abuse as abusive)
It's an epidemic and yet we are only just considering compulsory therapists in schools. We sometimes have to fight to provide more than 6 sessions of therapy without having to refer elsewhere