Hey [@SirBeowulf]? While I'd say it wouldn't be unlikely for a student to try and knock the medal down rather than building up to it I'd think that the teacher would expect that some cocky student would try and put safeguards in place to prevent it. I'm not saying it would be completely impossible, far from it but I'd would assume that it would be more difficult than simply chucking a small cube at the crossbeam. Most crossbeams are made out of a very solid wood like oak and if I was the teacher in order to prevent people like Aurellius from doing exactly what he did I'd have the medal hung by chain and physically screwed into the crossbeam. Not something that would be easy to dislodge or break with just a simple weighted cube. [@Lugubrious] care to weight in?