IS school still a place of learning?

What an intense week this last one has been for me. When I look back I wonder how I made it. As a student teacher we want to do things properly and when we plan lessons we tend to PLAN the hell out of them. They can take up to four hours to compile, if you include an activity and well-thought out lesson plan material and ideas to keep today's children interested. I had five lessons, some of which I had to repeat to another class in the grade. Five lessons over five days meant planning into the wee hours of the morning most days. It was exhausting but I absolutely love teaching so it just seemed to be worth it in the end. I had to give one class a serious talk about their behaviour in my classes. Their register teacher had been so upset with them because of how badly they had been behaving in the last week, and they did the same in my class with their incessant talking and devil-may-care attitude towards their work. When they found out that their behaviour was causing me to do poorly in a lesson that is being assessed (yes, they don't know that us student teachers are actually there to be ASSESSED), they changed their attitude because although they were chatty, they seem to genuinely like me, and continued to behave in the rest of the class, for which I am grateful. I thanked them afterwards for understanding.

One thing that stood out to me this week was the fact that there are so many things going on in that school that the teachers are aware of but choose to turn a blind eye to because either they know that they are fighting a loosing battle or because to take action is simply too much effort. Once the rain had penetrated some of the prefabs that I work in, we were forced to move to the old section of the school that had been scheduled for demolition but still stood for some reason. These classrooms obscure the view of the back of the school and the abandoned tennis courts behind the school. As I was sitting in class one break time I saw something that ignited an anger within me - streams of children walking on a mission to the abandoned tennis court walls. I had one thought at what they were doing and I was right. I decided to go and investigate and to my horror, the smell of marijuana hung heavily in the air with cigarette smoke and who knows what else. I took one look at the mass of about 80 children hanging in masses hidden by the abandoned tennis court walls. They become high during breaks and then we have to deal with children who are absolutely unable to take anything in. The smell of marijuana stinks of failure and lost opportunities.

I spoke to my mentor teacher about this and she told me that they are aware of the problem but something is being done. The worst punishment a child can get would be detention which they seem to enjoy because all their friends are there too. My heart breaks for these children in masses throwing their lives away for a fleeting feeling. It makes no sense to me. The next day I saw that not only are these children smoking weed, they get SOLD weed by people who sneak in through the gates and sell these drugs to school children. Men in hoodies, who are obviously gangsters. One I saw walking with a scissors - not to cut out pictures from a magazine I can guarantee you. It just breaks my heart because there are young girls on the grounds, and impressionable young boys who are put at risk by these gangsters and strangers on a school premises that should be a safe haven for any child. This is totally unacceptable and I intend to write a letter to the head teacher to report what is going on.
My heart breaks for these children and I feel like I have my hands tied. Is school still a place of learning or just a place children come to smoke, socialize, get high and do the bare minimum? Am I looking at this the wrong way? What can be done? Where do we go from here?