What does nth grade reading level even mean?

Very broadly, a lower grade of reading level means:

Less broad vocabularly,

Less ability to use and comprehend more complex grammar and sentence structure,

Less critical analysis capability,

Less ability to understand context and domain specific, different meanings of words,

More reliance on nebulouy defined, vague slang vocabulary.

In the context of adults I can understand, but I think I've heard things like Xrh graders having an average reading level as Yth graders.

This means that say, a typical 8th grader now has reading/writing abilities on par with a 6th grader.

In other words, kids keep failing classes and getting passed onto the next grade anyway, instead of being held back, or sent into some kind of 'catch-up' or 'remedial' classes to get them up to standard.

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Teachers and the education system broadly have, you know, rubrics, standards, lists of concepts that a kid is supposed to be taught in each class and grade.

This is how 'grading' works, the idea is that your test is supposed to evaluate how successful the student was at learning, how succesful the course was at actually teaching the student new concepts.

The main problem is that we underfund teachers and schools, and also punish teachers and schools when they actually do the right thing and refuse to pretend a kid has learned things they haven't.

So, the result is, kids don't learn.

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