PICC's are super easy at home. I refuse to be admitted unless it's really necessary. They are sturdy and easy to use. I continue going to work and classes while infusing all the time. I recommend the pressurized cannisters, too, as they are small and portable. I got one of those cast covers from the drug store for showers, and I either wear long sleeves or cut the feet of socks and use the tube as a cover. People ask questions, but I'm not embarrassed by it, and the sock keeps people from freaking out at the sight of a tube in your flesh. When I was young, my parents set up a "medical table" in the corner of the living room and kept it a semi-sterile area. They hooked me up and sent me out to play (gently, of course). By the time I was 12, I could do most of it without help. Adding an extension tube to the port gives you more independence (if you son is interested in flushing and infusing without compete dependence on you).
The only thing that totally bummed me as a kid was being unable to swim, but most other things were still okay. I pulled out a PICC once by jumping into bed and getting the cord stuck under the wheel of my IV pole. Your son will have to learn to be more careful than usual, but it comes easily enough. The single greatest thing my parents ever did was make it seem as normal as possible (not hiding it, allowing me to be nearly as active as before, establishing routines).