When she entered the room, she found them pointing to a seat near a window, behind a small desk.
There were desks all over the room at regular intervals, and a larger desk up in front.

Almost all the people sat at desks.
There was a curious wooden box in front at one side of, the big desk, and a girl sat before it pushing down some black and white strips that looked like sticks, and making her feet go, and singing with all her might.

The curious box made music, the same music the people were singing.

Was it a piano?
she wondered.

She had heard of pianos.