I think the contrast between your approach and the Orff method is quite interesting. I admit to not being a fan of Orff as a person and I used to like his music more than I do now.

I find the Orff instruments interesting and there is at least one manufacturer in Germany, Sonor, that makes very high-quality versions of them. On the other hand, I had a book out of the library about the method and it was huge and full of theory. And it wasn't just the one book, it was part of a whole series. I thought and still think, that anything that needs this amount of theoretical underpinning has to be BS.

There's nothing wrong with pentatonic, but it's one of those things where you can't go wrong: Multiple people can noodle simultaneously all day and nothing will sound too awful. That's not what I call music, though. Sometimes I hear music and I think that it goes up and down but it doesn't go anywhere. Often with jazz solos, especially free jazz, before I switch them off.

Orff was big on improvisation but he didn't like jazz or popular music and didn't include it in his system, whereby jazz was the one kind of contemporary Western music where people were improvising. And I think what he did choose as repertoire seems very corny nowadays.

I think what you're doing is great and may well inspire many kids to want to make music. This isn't a criticism, but there is kind of a leap between making noise (or sounds) on instruments and practicing drum rudiments or learning to play the guitar or the piano or another instrument. However, that's where parents and teachers come in.