In this example, "to be spared" means "to avoid" or "to not be included in". Today we will hear whether the school is to be spared from closure. Today we will hear whether the school will avoid being closed. Today we will hear whether the school will not be included in a list of closures.

That sentence means that today they will hear whether the school is forced to close. The word "spare" means to get out of unpleasant circumstances

to spare a life If you win a battle you get to kill your oponents. But sometimes you don't do that. We say: I will spare you life. to be spared something = to be excluded/saved from something The school may be excluded from closure (which is iminent).