They should at least be safer at the school than anywhere else. Assuming they didn't drain the bunker totally. I thought they couldn't take all the supplies when they fled.
The nuke is definitely bad news but remember they go to a bunker underground so if they stay in till the bomb drop then they're probably safe. I do hope it what it gonna happen and well that probably mean that the others girls are done for depending where the bomb drop and the power of it. Skipping the april issue is bad for my heart, i want to know if my girls gonna survive ad i hope what Miki forgot is not that important really but it seem like it is, tho it just could be her friend like @Ominous said.