Okay, I'm not sure if this is how the game is setup, but I got to something like Day 12 and was never allowed to explore at night. I was told about a mansion and to stay over at a girl's house and neither option was ever open for me to select.
The only thing i can think of that might have happened is I took a gym class prior to the message about classes starting to rotate in the first classroom? In case that broke some triggers in the game that should probably be disabled if so.