Shouldn't a "school teacher" know the difference between a zygote and a child?What's the difference between a human life and a human being?

Since you aren't one, let me help you:
The shit you took this morning and flushed is "human life". It contains living human cells just like those you wash down your sink drain when you clean your dentures and rinse with mouth wash.
A human being is defined here: https://www.law.cornell.edu/definit..._occur=1&term_src=title:1:chapter:1:section:8