Was pretty fun! It wasn't as scary as I think the title or the in game title said, but the environment and sounds really made it spooky and sold the dark aesthetics well! The work you put into the buildings outside of the school was impressive (A lot of games usually just have a void.) The work you put into the classrooms was also very cool! (Video below if anyone's interested!)
The phone messages was pretty neat but the phone I thought looked a bit weird at the edges, but having the other person give exposition was not bad; it gives the player incentive to explore. Maybe to expand on that, make more messages appear if the players take too long? It would make it scary as there would be random message notifications that would pop up, etc.
The two shadow kids that appeared were pretty cool but there was a lack of story behind them. It's not that hard to understand why there are ghosts there, but the lac of story behind the kids didn't make them scary but they did add to the environment overall! There was no build up to the scariness; maybe make the player roam around the school more or maybe the stuff they had is missing and they have to find it in another classroom; this would make players explore as well as add opportunities to add spooks and scares!
Also might want to change the title as the in game title was different than the one in the site.
The above are just suggestions and only my opinion, but it was a cool game in the end but could definitely be more! Great short game especially done for the first time!