In our Year 9 SATs it was really hard not to laugh because the invigilators were so bored after walking round the room for an hour that when my friend put her hand up to say that there was a wasp at the window about 5 invigilators came over and were trying to get rid of it all at once lol. In my maths mock a few months ago we were in a classroom rather than the hall and it was lesson changeover so people in other years were walking past talking going to their next lesson and the teacher, rather than just telling them to shut up, stood with the door half open and every 5 seconds exactly opened the door (on its very noisy, rusty and squeaky hinges) said "SSSHHH!!" really loudly, then closed the noisy door again. She repeated this like 20 times until we were all laughing- it was honestly the most distracting thing ever- much more distracting than just the people talking.