I was thinking of concepts regarding Melody.
Keep us up to date on your own ideas and what you think you'll be going with. Rounds are fun and are based on just a single usually simple melody. Learning them, practising them, arranging them and of course performing them is always lots of fun!Singing, and listening to musical recordings or you playing the piano would be the way to go with a group of 17 and only one piano. Even if you had more keyboards, it would be a bit of a shamozal if they weren't used to playing. Is this demonstration you have to do just a once off thing, or will you be taking the class a few times?How long does your demonstration have to last? For the entire lesson, or just a part of it?Do you teach in schools usually Liezly or will the school environment be new to you?