Just leave it alone... unless you have an ally or allies, in the upper branches of the school.
My friend worked at a school like that... and they/she had the SAME problems. Most schools do.
But, the school Director/Board members/upper staff members... ALL have various degrees of politics and issues and what not.
And the bottom line is: the school did nothing about it all.
You can drag the horse to the trough, but you can't force it to drink.
And yes, you can seem like an annoying employee.
It is sad.
You see legitimate issues. For which you constructed valid solutions.
But in the end, you cannot make them heed to it nor listen to it.
IF you mention the report you came across... they will wonder why you are doing that.... trudging through old reports. They will not see your line of thinking, about it.
Anyway, my friend no longer works at the school she was at. And since then, the school is really not a highly successful run school.
The Director of any school... has to lead the ship. Not all can.
A Director... will not always listen to a staff employee... and it will make her look, inept. They will not risk that.
AND IF YOU GO above the Director's head.... and by pass her/him... you will be seen as a troublesome staff member and as someone who is 'embarrassing' the Director.
You NEED to be aware... of things like that.