This requires some effort, but if a number of you can convince your parents that you need a pocket mirror for a class project (on the speed of light, or the science of reflections, or something like that), then you can faithfully reproduce the searchlights from a concentration camp.
If the lights land on anyone, in particular someone haplessly entering your class, you can then divide into two groups - one howling like an alarm, the other barking like guard dogs.
This will make the person entering the room feel as awkward as it is possible for humans to feel.