She might be rescued by a kind neighbor who gives her a towel to cover up and then helps her get back into the place. For example, if it was an apartment building, the neighbor could call the landlord to open the door.
First, I would find something to cover her up, like a blanket or a large piece of cloth. Then I would try to find a way to get her back inside or find a safe place for her to stay.
Perhaps she was at a public pool changing area. There was a sudden commotion like a false alarm of some sort. In the chaos, she got locked out of her changing stall while naked. It could be really embarrassing for her and she would have to quickly find a way to get some clothes or cover up.
One possible reason could be a cruel prank played on her by someone. Maybe there are some mean - spirited people who want to embarrass or harm her.
A kind neighbor might see her and offer help. They could call her parents or try to open the door for her if they have the right tools.
She could look for any loose objects in the basement to pick the lock if it's a simple lock. Maybe she could find a hairpin or a small piece of wire.
Maybe she was accidentally locked out while playing in the yard without shoes. She might be waiting for someone to come back and let her in, feeling scared and cold.
No, it's not. It's usually a fictional story made up for entertainment or to convey certain themes and messages.
Some characters would panic. They might start crying or running around aimlessly, not knowing what to do. They're just in a state of shock at being locked in the school.
We can offer her privacy. Immediately ensure that no one else sees her in that state and find something to cover her up. This simple act can start to ease her embarrassment.
One possible reason could be that she was kidnapped by a criminal who wanted to keep her hidden for ransom or other malicious intentions. Another reason might be that she was being held captive by someone with a mental disorder who had an abnormal obsession with her.