Teaching G and M Code, I guess not?

So I like to teach G and M Coding and thought, hey I have a cnc router I could use. We always start out with the basics and I have students hard code (text file, using coordinates from their drawing) to understand what the code is doing. I am finding out through this forum and others GRBL doesn’t really do arcs but a whole lot of little line segments. We eventually get to CAM software and will probably not have so many problems. Is there a free converter that takes basic G and M Code and converts it to GRBL. This way I could still teach the G and M Coding and then they could see how it works even though it isn’t exactly what they programmed?

Grbl does support G2 and G3 arcs — I hand-coded some ages ago:

https://wiki.shapeoko.com/index.php/File:Circle-diamond-square-50-45-40mm.txt

If you want to teach programming you’ll probably want to do loops and variables — there’s a pre-processor for that: