[@KactusPunch]  I do love the age of the climate and the global warming. I am a bit of a science freak. But since you mentioned that you want to to make no high tier alien subplot, and the social dynamics

What if the detention school is actually not really a detention school, but a place where children are set out to recover water (there is actually water on the moon) and minerals such as oxygen, iron, silicon and stuff from the moon soil called - Lunar Regolith(its an actual thing). 

But there can be some sort of internal conflicts between some of the staff who think that children even though they are mischievous and troublesome shouldn't be doing stuff like this. But on the other hand some staff members might also actually insist that the kids should be doing stuff like (what if the reason behind this is because they were also once students of the same school and don't know how to handle their trauma). 

There can maybe be different teachers for different class (mining for water, extracting regolith, sorting the regolith into the different mineral, maybe even packaging because they have to send it back to the earth that needs repairing from the impact of climate change). Their can be a point system where each student is ranked, and maybe the hgihest rank can get a trip back to earth and get out of the detention base. 

Becuase its only 1 student in the entire school that can be allowed to leave the base competion will be tough. Some becomes friends but later get betrayed, others have trust issues and so on.


maybe a plot twist - what if in the case that the first position rank is tied with other people, then they do like a match of some sort like the hunger games where it is literally just survial through and through or you get injured (maybe even die). 
Similar to hunger games where teh rich people on earth can maybe if they like the player they will send a food parcel or something ...


Let me know what you think about it