But there's probably some extraneous stuff as well. I mean, when you mention schedules, I can almost remember what my middle-school schedules looked like, it triggers thoughts of the faces of my middle school teachers and particular classes I had... but then I get bowled over more by non-tangible thoughts about the teachers and what my experience was with them... things I normally don't think about but just popped back into my head. Usually I remember the most if my experience with either really good or really bad.
The brain is basically taking in a lot of input and it gets dropped into those memory locations / gets imprinted just because it's like a security recorder/camera. if stuff isn't overlaid by other memories, it will linger just like scraps of data from "deleted" files in a hard drive.
... and of course I'm just making all this up, but it sounds like a potentially sound theory, doesn't it?