Oh, I didn't know that.
It's still impressive how many different stories people manage to tell by always using the same assets sets.
Yeah, in this particular case, PlayHome is a game, that allows you to set up your own scenes, using the sets that come with it, or ones that are converted to work with it. While it has a scene editor, the assets that came with the game, including the school rooms, are not really designed to be edited, and most of the parts are all one solid object, for the sake of what you can do with it. And worse, exporting those things, is ...complicated at best. So, the only way to fix the clock, would be to make every room from scratch, decorate them, bake textures, try to match what is there, and not look bad, without making it a lot more resource intense.
There are a lot of good things about it, like the built in animations, and 0 render time, but there are also many limitations as well (like being almost impossible to good looking male), so it's give and take.