The vandalism to the Torch included a broken pillar. This would have required heavy machinery or super strength to achieve and would have rendered the room, and the rooms above it, unsafe for students.
When Clark is thrown through the window, the glass breaks before he comes into contact with it.
After Clark is dumped into the blast furnace and the thieves make a getaway in their truck, you can hear the sound of an accelerating engine as it's driving away, but the brake lights are on.