This really resonated with me. I taught computer science to middle/high school aged kids for several years, and had similar dilemmas on how to keep everyone engaged. There would always be a wide range of student aptitude, and it was always a bit discouraging to see how many students aren't ready to learn. But it's pretty awesome nowadays to get messages out of the blue from my former students entering the workforce and thanking me for the course.

I am sure one of your students will build something amazing with Rust some day, because they worked on a practical application and had the resources to "level up" on this very useful skill. Hopefully they send you a message about it :)