At 8-12 weeks, they may be on the young side to eat too many scraps, but it's good to start offering at this stage.
When I give mine scraps, I give most scraps whole...bananas (peeled), apple cores, peels of pretty much any kind, etc. About the only stuff mine have trouble with is root veggies...
I've given my chickens most kinds of meat. The only question with ham is how salty it is...too much sodium is very bad for chickens. So, it's not the meat, it's the salt.
I feed my girls probably 90% food and garden scraps, 10% layer pellet. I had a good score yesterday at work...after a pot luck, I ended up coming home with a full sized disposable steam tray pan full of veggies, pasta, hummus, and a few other bits and pieces.