I'll probably set him up with a 35mm camera on holiday this summer. For the large-format stuff I've got plate cameras that are compact enough for him to help with in a reasonable way; but this is from an 8x10 with a 21" lens, and you have to rack that thing WAY out to focus on anything closer than, like, Neptune. I couldn't reach the front standard from under the darkcloth, and I'm 6'2" with long arms.
I was a little older than he is now when my dad had a darkroom in the basement, and I remember having a great time in there, being curious about the different chemicals and thinking the safelight and the glow-in-the-dark timers were really fascinating. I think I need to switch back to an acid fixer now, because the smell of rapid fixer is one of my favorite memories of that time, and I don't think anyone is going to form heartwarming happy memories around the ammoniac scent of TF-4!