I only asked because although it is possible to do it in Photoshop, it is anything but easy, and definitely not part of a workflow that you want to have your kids learn.
If you want to create cut lines, you need a vector drawing program. The two most commonly used are Adobe Illustrator (which costs a lot) and Inkscape (which is free.) Alternatives are CorelDraw and Affinity Designer, and those are mid-range in price.
I’m going to give you a list of tutorials that might help you to put together a plan of options…most are just a couple of pages, but they explain how the Glowforge interface works and what it is looking for from the design side.
Here you go:
Then if you want to get them started doing their own stuff quickly, the Matrix has a lot of tutorials and video links showing the best of the tips and tricks for individual design programs:
For using the Glowforge:
For Using Photoshop, GIMP and Paintshop:
For using Illustrator, Inkscape, CorelDRAW and Affinity Designer:
For using Fusion 360, OnShape, Openscad, Rhino, etc.
