Even though the Recycling Plant was replaced by the School, this stamp could still be earned in that room by throwing snowballs at/near the fish skeleton model hanging from the ceiling of the room, due to the coordinates for the stamp being retained.
It has an oval shape similar to the Activity stamps, even though it belongs to the party section of the Stamp Book. This is also the same case of the Tree Mob stamp.
Gallery[]
The coordinates at the School, from which the stamp can be triggered