Mafia as a trigger
You cheat at a game of Mafia (or Werewolves, if you know it). For a description, see https://www.kefkefkef.com/games/61dcbe4a9623669489619fab/ The narrator decides, by tapping, who the characters are. You can cheat very easily - make all the madrichim the characters you want them to be. You can decide what characters you want - whether you want a 'Who killed <Joseph>' scenario, or just who stole x, or who learnt y. You could give the game a themed title so that everyone knows it's leading up to a peulah, like 'Mafia Rabbis'. It's very flexible, but the essentials are the hanachim think they're playing a game of Mafia, and to their surprise all the characters are who you want them to be, and they can stand up and talk their pieces. Try for some variation, but only if you've played Mafia or Werewolves with the children before.