If you mean physical safety from intruders or terrorists, then I guess no place is ever totally safe. But for the last few years, most schools (in America anyway) have taken huge safety measures, installing security systems and having guards, etc....
If you mean physical safety AND emotional safety, then the first good step would be to fire the Head of Education Arne Duncan and his minions like Kevin Jennings, and THEN to make the Superintendents and teachers monitor the kids' activities much closer, teach the teachers how to actually guide students.
Years ago, the teachers' motto was for kids to report it if someone bullied them, 'cause they weren't supposed to fight back; if a child returned the "favor" and hit back, they were also in trouble along with the instigator.
Then, somehow, the motto became "Don't Tattle"! So what are the bullied kids to do? Take up for themselves!
Those mixed messages coming from the authorities in schools took away the reasoning abilities of the students in many situations.
....And I see from your profile you're not in the U.S.?
So, what is it that kids in your schools need protection from?
Many. The mere presence of rickety chairs offer a risky situation. If teachers are not sensitive to this basic need of a child in the classroom, much so with the school administration, school children might experience uncomfortable, and of course not be doing well in their class.