The Viennese Vegetable Orchestra play instruments that they make out of vegetables (with the occasional kitchen utensil thrown in).
Most schools (at least when I were a lad) give their pupils a music class each week.
Once every few weeks, or perhaps for a whole term each year, this could be a
veggie music class.
If nothing else, this would surely be more motivational than a normal music class simply due to the pure silliness of it, but here's a musical scaleful of other benefits:
A: Cross-disciplinary learning opportunities. The students could go from music to cookery class, cooking the vegetables they used that week. Science classes could explain how the vegetables produce their sound, or test the strength of different instruments. Maths classes can calculate how much it costs to stock an orchestra.
B: Musical confidence. Students will feel freer to play and create sounds, since there's not a sound they're 'supposed' to play in the same way that there is with traditional instruments. This willingness to try and experiment could give them added confidence when they do start to play other instruments.
C: Craftsmanship. Having to make their own instruments is a quick and easy way for students to try their hand at something practical, compared to woodwork or metalwork classes.
D: Teamwork. One vegetable instrument by itself can only sound interesting up to a point. Students learn that combining their efforts produces the best and/or funniest results. More advanced students can try to emulate various different styles of music, from classical to electronic to house.
E: Familiarity with food. Students will discover that fresh vegetables work better than rotten ones. They'll get used to handling and preparing fresh food. They could also be encouraged to bring their own vegetables for each lesson. Even if they still prefer burgers given a choice, at least veggies won't be a totally foreign food to them.
F: Curiosity. Who knows what a carrot flute sounds like? Okay, so you do, because you made a carrot flute last month too. But you still don't know what *this* carrot will sound like. There's a sense of new possibilities every lesson, which again isn't always there with traditional instruments. And it'll quite possibly encourage kids to look at other everyday objects with open eyes, too.
G: Fun! Fun fun fun! Come on, you can't tell me you don't want to try this! Yummy crazy messy veggie musical madness!