why the heck are my teachers giving me homework when humanity is going to be destroyed?

I agree, pandemics are very stressful and we shouldn't be prioritising algebra homework. But, there is not much under 18s can do to 'help' right now so focusing on the important years of your education to then take exams is still a focus. After all they are the future. 

Why the heck do you bother to post this question when humanity is going to be destroyed?

I teach online math.

Humanity is not going to be destroyed, and then you will need to live in a world where people are educated.

You need something to keep you busy before humanity get destroyed. 

Yes, I am a teacher. What the teacher assigns will be relevant to the goal of that class for that year. It also builds a foundation for a class, or two, that you will face next year. That class will be understandable if you have an understanding of ALL the classes from this year. It grows and becomes harder just as math....addition, then subtraction, then so on.

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I am not a teacher. I am not convinced that humanity will be destroyed. Yes, that could be possible, but you still have to do your home work.

The people who posses greater intelligence might be able to survive. People like Donald Trump (USA President), and China's president are nothing more than f**king clowns, so you don't want to be like them, or perhaps you would prefer to be a bum, and not do anything. I suppose that would be better if that's what you want to do with your life!

Humanity goes through crises every now and then (WWII, the Spanish flu, the Great Depression, etc.), and generally it emerges better and stronger. The world we knew came about as a result of WWII. Now, this pandemic is terrible and the state of the world is bad, but ultimately good people all over the world will ultimately rise up and prevail, and when that happens there will be a transformation that will make the world a better place. 

Because humanity is not being destroyed.  Humanity has withstood much bigger pandemics than we have now. People will be building immunity from being infected. Do a Google search on the "Spanish Flu" for example.

The dead are perpetuating the dead subject to rebirth in anamnesis prevailed by dark light of time immemoral due to the proclevties of mind - They eat flesh with flies unawares attracted to the neon lights in hats and slick shoes with the bow ties whom also let them in waxing skins in disguise - And by working in the pretence of being someone I say I am not will be subject to this.

The dead are spiritual dead, but did acquire the world.