Hey, we all have lucid dreams from time to time. The thing I have come to understand is that the location in your dreams is the most significant, so in your situation:

SCHOOL HALLWAY

So…

I suggest you visit that hallway someday soon. Find a comfortable place to chill. Take something to read and a bottle of water, or whatever you need to feel comfortable, and just spend some time there to work out what is it about the location that has entered your subconscious.

I may be wrong, but I think you just need to feel at ease in that place, so just go there, take some time out. No problem, right?