I love that kind of stuff. I think it's a ton of fun to do that.

Ulhiker did a presentation on this a couple months ago at a hiker's gathering here. I missed it, but everyone there was pretty impressed with it.

I think he focused a lot on lightweight gear and demonstrating how and why it worked. He has some fairly high-end gear, and that was appropriate for the audience there, but that might not be the case with yours. I think that if you do discuss and display any high end gear you might want to also discuss a low cost alternative that works well too. In any case, I'm sure he'd be glad to go over it with you and give you some tips on what people responded to.

With your audience, I think it would be good to talk about the technique. Discuss how there are different styles and approaches to backpacking. If most of them are surrounded by bush crafters then explaining how that is one approach, and how they can experiment with other approaches, such as ultralight and lightweight backpacking, and benefit from them all and put them to use in various circumstances and conditions.

Talking about how to figure out what you really don't need is, I think, the first thing one needs to learn about UL backpacking and that this, and not just gear, is central to the concept, and how having everything you need is the core element of that. That differs a lot from the bushcraft approach, in that the goal there is to have the tools and skills to acquire everything else you need.

Anyway, be sure to have fun with it. You might start off by asking them "What's the heaviest thing you carry in your pack?" That will get them thinking. And then you could follow up with, "What's the dumbest thing you've ever seen someone bring?" That should get them poking fun at each other and engaged in the topic.

I'd offer that you leave them with some cheap and easy DYI gear ideas so they can put what they've learned into practice. I'd think a SuperCat stove would have to be a big hit with them (not so sure about their parents), and so would a visqueen tarp.

You have to let us know how it went. Kids generally crack me up. I was hanging with my grandson and a group of scouts when Ulhiker did his presentation and those kids were as sharp witted and funny as any crowd I've been with.