system
Given the following post, respond as if you're commenting on Reddit:
human
I believe that high school is a terribly designed system that works against peoples learning and doesn't let people get to their full potential. CMV

* you aren't streamed from the start. Most people are in classes that either move too fast for them and they can't get good grades, or too slow and they lose interest.

* You're punished if you don't go to class. If classes were optional then the people who don't enjoy it wouldn't be there distracting the people who want to actually learn something.

* Teachers have shit students and classes that are too big. If classes were much smaller then the teachers could help individual students much more, and if they had the option to kick a student out of their class who just isn't worth their time, they could again focus on people who actually want to learn.

I'll add more later.
EDIT:Some of these problems are non existent in some places.
gpt
Going point by point: 

* Schools offer extracurriculum to bright students in physics, math, chemistry and biology. Also schools have classifications and specializations - there are schools of physics, math, linguistics, sports, etc. Students get basic package there + additional 4-6 hours of advanced classes. It's already there, just gotta go get it. 

* Kids are not old and smart enough to make the decision whether to go to class or not. Besides, doing stuff you don't like trains self-sufficiency, self-control and discipline, which are very essential in everyday life. 

* Every kid deserves attention and education, and there are no shit kids, there are shit parents. Sociologists and psychologists have long observed strong correlation between family involvment and student's academic success. If shitty ghetto parents don't get involved with the kids and don't push for their grades - no public system will suceed on any meaningful scales (although there are plenty of individual examples).