Play some trumpet fanfares to your kids, asking them to notice what they all have in common. Hopefully you’ll get a response re. ‘jumpy’ melodies. Explain that the original trumpets were ‘natural horns’ without any valves or buttons, so they can only play a handful of different notes (along the harmonic series). Have a look at different pictures of trumpets as they evolved. Play John Williams’ Olympic Fanfare and see what modern trumpets look like.